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Wednesday, December 30, 2009

Smoke Bomb Materials




The smoke bomb you would purchase from a fireworks store usually is made from potassium chlorate (KClO3 - oxidizer), sugar (sucrose or dextrin - fuel), sodium bicarbonate (otherwise known as baking soda - to moderate the rate of the reaction and keep it from getting too hot), and a powdered organic dye (for colored smoke). When a commercial smoke bomb is burned, the reaction makes white smoke and the heat evaporates the organic dye. Commercial smoke bombs have small holes through which the smoke and dye are ejected, to create a jet of finely dispersed particles. Crafting this type of smoke bomb is beyond most of us, but you can make an effective smoke bomb quite easily. There are even colorants you can add if you want to make colored smoke. Let's start out with instructions for the easiest/safest type of smoke bomb you can make:
Smoke Bomb Materials

  • sugar (sucrose or table sugar)
  • potassium nitrate, KNO3, also known as saltpeter (buy it online or you can find this at some garden supply stores in the fertilizer section, some pharmacies carry it too)
  • skillet or pan
  • aluminum foil
Once you've gathered your smoke bomb materials, it's easy to make the smoke bomb...
  1. Pour about 3 parts potassium nitrate to 2 parts sugar into the skillet (5:3 ratio is also good). Measurements don't need to be exact, but you want more KNO3 than sugar. For example, you can use 1-1/2 cups KNO3 and 1 cup sugar. If you use equal amounts of KNO3 and sugar, your smoke bomb will be harder to light and will burn more slowly. As you approach the 5:3 KNO3:sugar ratio, you get a smoke bomb that burns more quickly.

  2. Apply low heat to the pan. Stir the mixture with a spoon using long strokes. If you see the grains of sugar starting to melt along the edges where you are stirring, remove the pan from the heat and reduce the temperature before continuing.

  3. Basically you are carmelizing sugar. The mixture will melt and become a caramel or chocolate color. Continue heating/stirring until the ingredients are liquefied. Remove from heat.

  4. Pour the liquid onto a piece of foil. You can pour a smaller amount onto a separate piece, to test the batch. You can pour the smoke bomb into any shape, onto an object, or into a mold. The shape and size will affect the burning pattern.

  5. If you aren't going to clean your skillet immediately, pour hot water into the pan to dissolve the sugar (or else it will be harder to clean). Clean up any residue you may have spilled out of the pan, unless you want mini-smoke bombs on your stovetop.

  6. Allow the smoke bomb to cool, then you can peel it off the foil.
Now that you've made your smoke bomb, it's time to light it...

Homemade Firecracker Materials

Firecrackers are extremely easy and inexpensive to make yourself. You may want to make your own firecrackers because you are interested in learning how to make simple fireworks or it may be you are unable to obtain fireworks where you live. Fortunately, the materials needed to make your own firecrackers are very common.

Homemade Firecracker Materials

Toy gun caps are nice because the powder used in them is easy to work with. Here's how to get the powder out of the caps:
  1. Gently insert a pin or needle through the back of a cap through to the front.
  2. Remove the pin and re-insert it from the front, where you made the hole. Pry the powder out of the cap, tapping it onto a sheet or paper or plate or other working surface.
  3. Carefully work the pin around the edge of the cap to collect all of the powder. There is a very slight chance of popping the cap, so be gentle and work slowly.
  4. How much powder you need depends on the size of firecracker you plan to make. One ring of caps is more than sufficient to create a loud bang, but you really only need powder from about 3 caps for each firecracker. For the sake of safety, it's best to make one firecracker at a time (you don't need a big pile of powder).
Now let's assemble the firecracker.
One you have all of the materials necessary to make firecrackers, you are ready to start putting the firecrackers together.
  1. Take a piece of tape about 2" long and pick up the gunpowder on the sticky side of the tape. Evenly coat the tape until you either run out of gunpowder or else run out of stickiness.
  2. Place the fuse (about 2 inches long) so that it sticks halfway down the tape. The fuse does not need to stick to the tape.
  3. Roll the tape around the fuse. Take another piece of tape and tightly wrap your firecracker. Be sure to cover the bottom of the firecracker or else the opening will give you a small rocket rather than a popping firecracker.
Alternatively, you could just fold a 2-inch strip of paper in half lengthwise, pour the gunpowder into the fold of the paper, and wrap the paper around the fuse. The paper firecracker could be secured with any kind of tape.
 

Now that you have a homemade firecracker, you need to light it! This is basically the same as lighting any other firecracker. Make sure you light it on a firesafe surface, far from people or pets. Don't hold the firecracker in your hand when you light it. Firecrackers that you buy contain measured quantities of gunpowder. You can estimate the amount of gunpowder in your firecracker based on how many caps you used. You won't necessarily get a louder 'bang' using more gunpowder, but you will increase the potential risk of injury, so don't go crazy making big firecrackers. Have fun!

Make New Year's Fireworks


'm partial to smoke bombs, since they are easy to make and don't explode, but there are lots of other fireworks you can make for your New Year's Eve celebrati

What Happens If You Touch Dry Ice?

Dry ice is the solid form of carbon dioxide, which normally exists as a gas. It is extremely cold (-109.3°F or -78.5°C), so you can get frostbite from touching dry ice... but what if you just want to poke it or touch it for an instant? What happens if you taste it?
Here's the answer.

Answer: When dry ice heats up it sublimates into carbon dioxide gas, which is a normal component of air. The problem with touching dry ice is that it is extremely cold (-109.3°F or -78.5°C), so when you touch it, the heat from your hand (or other body part) is absorbed by the dry ice. A really brief touch, like poking dry ice, just feels really cold. Holding dry ice in your hand, however, will give you severe frostbite, damaging your skin in much the same manner as a burn. You do not want to try to eat or swallow dry ice because the dry ice is so cold it can 'burn' your mouth or esophagus, too.If you handle dry ice and your skin gets a little red, treat the frostbite like you would treat a burn. If you touch dry ice and get frostbite such that your skin turns white and you lose sensation, then seek medical attention. Dry ice is cold enough to kill cells and cause serious injury, so treat it with respect and handle it with care.

So What Does Dry Ice Feel Like?

Just in case you don't want to touch dry ice, but do want to know how it feels, here's my description of the experience. Touching dry ice is not like touching normal water ice. It is not wet. When you touch it, it feels somewhat like what I would expect really cold styrofoam would feel like... sort of crunchy and dry. You can feel the carbon dioxide sublimating into gas. The air around the dry ice is very cold.
I have also done the 'trick' (which is inadvisable and potentially dangerous, so don't try it) of putting a sliver of dry ice in my mouth to blow carbon dioxide smoke rings with the sublimated gas. The saliva in your mouth has a much higher heat capacity than the skin on your hand, so it isn't as easy to freeze. The dry ice does not stick to your tongue or anything like that. It tastes acidic, sort of like seltzer water.

Tuesday, December 29, 2009

Prevent a Hangover

The other day I mentioned a study that found the severity of a hangover is related to the color of the alcohol, which was a reflection of the chemical composition of the drink. There's more to hangover chemistry than just the color of the drink, however. For example, some people's biochemistry essentially makes them immune to hangovers. These people can detoxify the alcohol, acetaldehyde, and congeners quickly enough to escape most of the negative effects of alcohol consumption, except maybe the effects of dehydration, since the enzymes responsible for clearing the body of alcohol and its metabolites require water.

If you are not a member of that lucky 25-30% of people who don't get hangovers, you can minimize your chances of suffering by avoiding deeply colored drinks, staying hydrated, and limiting your consumption. Keep in mind, some alcoholic beverages contain enough contaminants that it's not the alcohol that gives you the hangover, so even one drink might be enough to make you sick. If you do find yourself suffering from your holiday celebration, there are several hangover remedies you can try.

Sunday, December 27, 2009

The Nobel Prize in Chemistry 2009

"For studies of the structure and function of the ribosome"



Photo: MRC Laboratory of Molecular Biology
Credits: Michael Marsland/Yale University
Credits: Micheline Pelletier/Corbis
Venkatraman Ramakrishna
Thomas A. Steitz
Ada E. Yonath
third 1/3 of the prize
third 1/3 of the prize
third 1/3 of the prize
United Kingdom
USA
Israel
MRC Laboratory of Molecular Biology
Cambridge, United Kingdom
Yale University
New Haven, CT, USA; Howard Hughes Medical Institute
Weizmann Institute of Science
Rehovot, Israel
b. 1952
(in Chidambaram, Tamil Nadu, India)
b. 1940
b. 1939





The Nobel Prize in Chemistry 2009

Prize Announcement





 Announcement of the Nobel Prize in Chemistry by Professor Gunnar Öquist, Secretary General of the Royal Swedish Academy of Sciences, 7 October 2009.

 

 

 

 

Interview

 Following the announcement, Professor Gunnar von Heijne told senior editor Simon Frantz how the achievements awarded the 2009 Nobel Prize in Chemistry not only provided insights into life at the atomic level, but also provided insights into how to save lives.

 

 


The Nobel Prize in Chemistry


In 1901 the very first Nobel Prize in Chemistry was awarded to Jacobus H. van 't Hoff for his work on rates of reaction, chemical equilibrium, and osmotic pressure. In more recent years, the Chemistry Nobel Laureates have increased our understanding of chemical processes and their molecular basis, and have also contributed to many of the technological advancements we enjoy today.

Sunday, December 20, 2009

All Nobel Laureates in Chemistry



The Nobel Prize in Chemistry has been awarded 101 times to 157 Nobel Laureates between 1901 and 2009. Frederick Sanger is the only Nobel Laureate who has been awarded the Nobel Prize in Chemistry twice, in 1958 and 1980. This means that a total of 156 individuals have received the Nobel Prize in Chemistry. Click on each name to see the Nobel Laureate's page.

Jump down to: | 1980 | 1960 | 1940 | 1920 | 1901 |

Sunday, December 13, 2009

Green Fire Instructions


It's easy to make brilliant green fire. This cool chemistry project requires only two household chemicals.

Green Fire Materials

  • Boric Acid
    Medical grade boric acid can be found in the pharmacy sections of some stores for use as a disinfectant. It is a white powder. It's not the same chemical as borax. I used Enoz Roach Away™, which is 99% boric acid, sold with household insecticides.
  • Heet™ Gas Line Antifreeze and Water Remover
    Heet™ is sold with automotive chemicals.
  • Metal or Stoneware Container
  • Lighter
Instructions for Making Green Fire
  1. Pour some Heet™ into the container. How much you use will determine how long your fire will burn. I used about a half cup of Heet™ for approximately 10 minutes of fire.
  2. Sprinkle some boric acid into the liquid and swirl it around to mix it up. I used 1-2 teaspoons of powder. It won't all dissolve, so don't worry about some powder at the bottom of the container.
  3. Set the container on a heat-safe surface and ignite it with a lighter. I have a video of green fire, if you would like to see what to expect.
Green Fire Tips & Safety Information
  • Boric acid is a relatively safe household chemical. You can rinse the residue remaining in the container down the drain.
  • This is an outdoor project. There isn't a lot of smoke produced, nor is it particularly toxic, but the heat is intense. It will set off your smoke alarm.
  • Be sure to set your container on a heat-safe surface. Do not follow my extremely bad example and set it on your glass patio table. Similarly, don't use any container that might shatter dangerously. Use metal or possibly stoneware, not glass, wood, or plastic.
  • Heet™ primarily is methanol (methyl alcohol). You could try this project with other types of alcohol. Possibilities include ethanol, such as vodka or Everclear, or isopropyl alcohol (rubbing alcohol). You might also try other common household metal salts for different flame colors.
  • For example, I susbstituted rubbing alcohol (isopropyl alcohol) for the Heet™. The result was a fire that alternated from orange to blue to green. It wasn't as spectacular as the Heet™ fire, but it was still pretty cool.
  • The green fire could be used as a stunning Halloween decoration in a cauldron or possibly inside a jack-o-lantern.
  • Keep the chemicals for this project out of reach of children or pets, since methanol is harmful if swallowed. Read and follow any safety precautions listed on the labels of the specific products you use.

Thursday, December 3, 2009

Branches of Chemistry

There are several branches of chemistry. Here is a list of the main branches of chemistry, with an overview of what each branch of chemistry studies.


The science of chemistry is divided into

several disciplines or branches of chemistry.

Ryan McVay, Getty Images


Agrochemistry
- This branch of chemistry may also be called agricultural chemistry. It deals with the application of chemistry for agricultural production, food processing, and environmental remediation as a result of agriculture.

Analytical Chemistry - Analytical chemistry is the branch of chemistry involved with studying the properties of materials or developing tools to analyze materials.

Astrochemistry - Astrochemistry is the study of the composition and reactions of the chemical elements and molecules found in the stars and in space and of the interactions between this matter and radiation.

Biochemistry - Biochemistry is the branch of chemistry concerned with the chemical reactions that occur inside living organisms.

Chemical Engineering - Chemical engineering involves the practical application of chemistry to solve problems.

Chemistry History - Chemistry history is the branch of chemistry and history that traces the evolution over time of chemistry as a science. To some extent, alchemy is included as a topic of chemistry history.

Cluster Chemistry - This branch of chemistry involves the study of clusters of bound atoms, intermediate in size between single molecules and bulk solids.

Combinatorial Chemistry - Combinatorial chemistry involves computer simulation of molecules and reactions between molecules.

Electrochemistry - Electrochemistry is the branch of chemistry that involves the study of chemical reactions in a solution at the interface between an ionic conductor and an electrical conductor. Electrochemistry may be considered to be the study of electron transfer, particularly within an electrolytic solution.

Environmental Chemistry - Environmental chemistry is the chemistry associated with soil, air, and water and of human impact on natural systems.

Food Chemistry - Food chemistry is the branch of chemistry associated with the chemical processes of all aspects of food. Many aspects of food chemistry rely on biochemistry, but it incorporates other disciplines as well.

General Chemistry - General chemistry examines the structure of matter and the reaction between matter and energy. It is the basis for the other branches of chemistry.

Geochemistry - Geochemistry is the study of chemical composition and chemical processes associated with the Earth and other planets.

Green Chemistry - Green chemistry is concerned with processes and products that eliminate or reduce the use or release of hazardous substances. Remediation may be considered part of green chemistry.

Inorganic Chemistry - Inorganic chemistry is the branch of chemistry that deals with the structure and interactions between inorganic compounds, which are any compounds that aren't based in carbon-hydrogen bonds.

Kinetics - Kinetics examines the rate at which chemical reactions occur and the factors that affect the rate of chemical processes.

Medicinal Chemistry - Medicinal chemistry is chemistry as it applies to pharmacology and medicine.

Nanochemistry - Nanochemistry is concerned with the assembly and properties of nanoscale assemblies of atoms or molecules.

Nuclear Chemistry - Nuclear chemistry is the branch of chemistry associated with nuclear reactions and isotopes.

Organic Chemistry - This branch of chemistry deals with the chemistry of carbon and living things.

Photochemistry - Photochemistry is the branch of chemistry concerned with interactions between light and matter.

Physical Chemistry - Physical chemistry is the branch of chemistry that applies physics to the study of chemistry. Quantum mechanics and thermodyamics are examples of physical chemistry disciplines.

Polymer Chemistry - Polymer chemistry or macromolecular chemistry is the branch of chemistry the examines the structure and properties of macromolecules and polymers and finds new ways to synthesize these molecules.

Solid State Chemistry - Solid state chemistry is the branch of chemistry that is focused on the structure, properties, and chemical processes that occur in the solid phase. Much of solid state chemistry deals with the synthesis and characterization of new solid state materials.

Spectroscopy - Spectroscopy examines the interactions between matter and electromagnetic radiation as a function of wavelength. Spectroscopy commonly is used to detect and identify chemicals based on their spectroscopic signatures.

Thermochemistry - Thermochemistry may be considered a type of Physical Chemistry. Thermochemistry involves the study of thermal effects of chemical reactions and the thermal energy exchange between processes.

Theoretical Chemistry - Theoretical chemistry applies chemistry and physics calculations to explain or make predictions about chemical phenomena.

Wednesday, December 2, 2009

Analytical Chemistry

These are the techniques and applications of molecular identification. Analytical chemistry lecture notes, laboratory exercises, organizations, journals, software, and additional resources are provided. Information is available for calorimetry, crystallography, electrophoresis, chromatography, and spectroscopy.

Introduction to Qualitative Analys

Identifying Anions and Cations


Qualitative analysis is used to separate and detect cations and anions in a sample substance. In an educational setting, it is generally true that the concentrations of the ions to be identified are all approximately 0.01 M in an aqueous solution. The 'semimicro' level of qualitative analysis employs methods used to detect 1-2 mg of an ion in 5 mL of solution.

First, ions are removed in groups from the initial aqueous solution. After each group has been separated, then testing is conducted for the individual ions in each group. Here is a common grouping of cations:

Group I: Ag+, Hg22+, Pb2+
Precipitated in 1 M HCl

Group II: Bi3+, Cd2+, Cu2+, Hg2+, (Pb2+), Sb3+ and Sb5+, Sn2+ and Sn4+
Precipitated in 0.1 M H2S solution at pH 0.5

Group III: Al3+, (Cd2+), Co2+, Cr3+, Fe2+ and Fe3+, Mn2+, Ni2+, Zn2+
Precipitated in 0.1 M H2S solution at pH 9

Group IV: Ba2+, Ca2+, K+, Mg2+, Na+, NH4+
Ba2+, Ca2+, and Mg2+ are precipitated in 0.2 M (NH4)2CO3 solution at pH 10; the other ions are soluble

Many reagents are used in qualitative analysis, but only a few are involved in nearly every group procedure. The four most commonly used reagents are 6M HCl, 6M HNO3, 6M NaOH, 6M NH3. Understanding the uses of the reagents is helpful when planning an analysis.

Tuesday, December 1, 2009

Dalton's Atomic Theory

These are pretty straightforward and require no explanation. Although you don't use these on tests or anything, it's good stuff to know (not to mention our whole understanding of chemistry is based on this):

Each element is made up of tiny particles called atoms.
The atoms of a given element are identical; the atoms of different elements are different in some fundamental way or ways.
Chemical compounds are formed when atoms combine with each other. A given compound always has the same relative numbers and types of atoms.
Chemical reactions involve reorganization of the atoms--changes in the way they are bound together. The atoms themselves are not changed in a chemical reaction.
These ideas form the basis of what a lot of AP Chem is all about; chemical reactions. It's nothing more than breaking some bonds and making some bonds, to put the atoms in a different order to create new things.

Intro to Atomic Structure

An atom consists of a nucleus and electrons orbiting around it. The nucleus is made up of positively charged particles called protons, and neutral particles called neutrons. The electrons are negatively charged particles.

Here is a simplified picture:



This atom has two protons (red), so it is a helium atom.

One thing that pictures like the above cannot express is the relative sizes of the nucleus and the atom. If the atom was really that big (diameter 108 pixels), then the nucleus would be 1/100th of a pixel big! Or on a bigger scale, if the nucleus was the size of a pea, then the atom would be as wide as a football field. Another thing is mass. Virtually all the mass is concentrated in the nucleus. The 'pea' would weigh 250 million tons!

There are two numbers to know about any atom. One is the atomic number, which is the number of protons (and electrons in a neutral atom), and the atomic mass number, which is how much the thing weighs. One proton's weight is close to one neutron's weight which is close to one. Electrons weigh virtually nothing when compared to the huge protons, so they don't affect the total mass. So the atomic mass number is simply the number of protons plus the number of electrons.

The notation of writing atoms is like this:



The top number represents the mass number.

The bottom number represents the atomic number.

Some things to remember while solving these types of problems:

(Note: Problems of this simplicity will not be on the AP test, I guarantee that. We are not so lucky. But you will be tested in class on this stuff.)

The bottom number is always the number of protons.
The bottom number is also usually the number of electrons, but only in a neutral element. Ions come later.
The number of neutrons is always the top number minus the bottom number. All you're doing is taking the total mass, taking away the portion that is due to the protons, and what you got left is the neutrons. Likewise, if you know number of neutrons and protons, to find this number all you got to do is add.
Example:

Sample Problem


Here is a sample atom. How many electrons, protons, and neutrons does it got?

Solution

The bottom number is always the number of protons you have. So there are 9 protons. It's a neutral atom, by the fact that there are no plus or minus signs anywhere, so you can assume there are 9 electrons as well. There are 19 total nucleons (protons and neutrons) in the nucleus, and 9 are protons. So there are 10 neutrons. Easy.

Elements

As mentioned before, an element's mass is determined by its protons and neutrons. The electrons, having almost no mass, do no contribute to the mass of an element. An element is defined by the number of protons and electrons it has. The number of nuetrons an element has, however, can vary from atom to atom. Each possible atom is known as an isotope. (ex. Carbon-14) If you go look at a periodic table, you will notice that each element has a given mass. This mass is an average of its isotopes. This does NOT mean that all carbons will have 6 protons and 6 neutrons (don't worry about these calculations, they'll make sense in the next chapter). Just remember that an element can have different number of neutrons, which will change its weight.

Protons, neutrons, and electrons

Elements make up compounds, and are considered the basic building blocks of matter. You cannot break down elements into smaller parts, but you can classify the different parts within the element. Within the element are protons, neutrons, and electrons. The neutron, a chargeless particle, can be found in the nucleus along with the proton, which is a particle only slightly smaller than the neutron but positively charged. Electrons are negatively charged and are found circling the nucleus (much like the sun and the planets in our solar system).
Within the atom, one can find a nucleus. The nucleus, which does not move around like electrons, contains both neutrons and protons. Both neutrons and protons have mass, and these two contribute almost 100% of the atomic mass of an element. Electrons, on the other hand, have almost no mass. Most calculations assume a mass of zero for electrons. Electrons, being so small, can move around very quickly around the nucleus. Protons and neutrons can also be broken down into quarks, but you won't learn about those petit particles in this chemistry year.
A common demonstration to show how little space the electrons and nucleus take up in the atom is with the football field analogy. If a football stadium was considered to be an atom, a feather on the 50 yard line would be the nucleus. That is how much empty space there is within an atom!

Biochemistry

Biochemistry includes molecular, cellular, and organismal chemical activities. Metabolic pathways and enzymology, biochemical structures and sequences, and genome databases are included.







Biochemistry is the study of
the molecules of life, such as DNA.
Ben Mills



Biochemistry is the science in which chemistry is applied to the study of living organisms and the atoms and molecules which comprise living organisms. Take a closer look at what biochemistry is and why the science is important.

What Is Biochemistry?

Biochemistry is the study of the chemistry of living things. This includes organic molecules and their chemical reactions. Most people consider biochemistry to be synonymous with molecular biology.
What Types of Molecules Do Biochemists Study?
The principal types of biological molecules, or biomolecules are:



  • carbohydrates

  • lipids

  • proteins

  • nucleic acids


Many of these molecules are complex molecules called polymers, which are made up of monomer subunits. Biochemical molecules are based on carbon.


What Is Biochemistry Used For?


Biochemistry is used to learn about the biological processes which take place in cells and organisms.

Biochemistry may be used to study the properties of biological molecules, for a variety of purposes. For example, a biochemist may study the characteristics of the keratin in hair so that a shampoo may be developed that enhances curliness or softness.

Biochemists find uses for biomolecules. For example, a biochemist may use a certain lipid as a food additive.

Alternatively, a biochemist might find a substitute for a usual biomolecule. For example, biochemists help to develop artificial sweeteners.

Biochemists can help cells to produce new products. Gene therapy is within the realm of biochemistry. The development of biological machinery falls within the realm of biochemistry.


What Does a Biochemist Do?


Many biochemists work in chemistry labs. Some biochemists may focus on modeling, which would lead them to work with computers. Some biochemists work in the field, studying a biochemical system in an organism. Biochemists typically are associated with other scientists and engineers. Some biochemists are associated with universities and they may teach in addition to conducting research. Usually their research allows them to have a normal work schedule, based in one location, with a good salary and benefits.


What Disciplines Are Related to Biochemistry?


Biochemistry is closely related to other biological sciences that deal with molecules. There is considerable overlap between these disciplines:



  • Molecular Genetics

  • Pharmacology

  • Molecular Biology

  • Chemical Biology

Wednesday, November 25, 2009

Standard State Conditions - Standard Temperature and Pressure

Know the Standard State Conditions
Values of thermodynamic quantities are commonly expressed for standard state conditions, so it is a good idea to understand what the standard state conditions are.
A superscript circle is used to denote a thermodynamic quantity that is under standard state conditions:
ΔH = ΔH°
ΔS = ΔS°
ΔS = ΔS°

Standard State Conditions

Certain assumptions apply to standard state conditions. Standard temperature and pressure commonly is abbreviated as STP.

  • The standard state temperature is 25°C (298 K). It is possible to calculate standard state values for other temperatures.
  • All liquids are pure.
    The concentration of all solutions is 1 M (1 molar).
  • All gases are pure.
  • All gases are at 1 atm pressure.
    The energy of formation of an element in its normal state is defined as zer

Friday, November 20, 2009

pHASE pH Adjustment Systems.

System Features





    • Skid Mounted
    • Turnkey Construction
    • Minimal Installation Time
    • NEMA 4X, UL 508
    • Small Foot Print
    • State-Of-The-Art Controls
      pHASE pH Adjustment systems are designed to handle a variety of acidic and alkaline waste streams including concentrated discharges. Any acidic or alkaline stream, of any concentration from any source can be safely and effectively neutralized with a pHASE pH adjustment system.
      All systems feature state of the art instrumentation and control systems using our proprietary "Optimized Batch" pH adjustment technology.
      Completely automated operation requires no operator attention other than periodic instrumentation calibrations and maintenance. Remote monitoring via SCADA, building management, or dial-up link available.

      Standard Materials of Construction*
      Treatment Tank: Polypro, FRP
      Reagent Tank(s): Polypro, PE, XLPE
      Pump(s): CPVC, Polypro
      Piping System: PVC, CPVC, Polypro
      *Alternate materials of construction available


    MODEL
    Max Average Flow* (GPM)
    Max Peak Flow* (GPM)
    Treatment Tank Volume (Gallons)
    Skid Dimensions
    pH05
    5
    10
    155
    40" x 40" x 60"(H)
    pH10
    10
    15
    360
    48" x 48" x 60"(H)
    pH15
    15
    25
    475
    34” x 65” x 60” (H)
    pH20
    20
    60
    475
    34” x 65” x 60” (H)
    pH30
    30
    90
    660
    44” x 85” x 62” (H)
    pH40
    40
    120
    660
    44” x 85” x 62” (H)
    pH60
    60
    180
    660
    44” x 85” x 62” (H)

    For higher flows see our labTREAT and batchTREAT family of pH Adjustment Systems.
    The labTREAT family is specifically designed for effluent streams typical of research laboratories, and semi-conductor fabs.
    The batchTREAT family is designed for high flows and highly acidic / highly alkaline effluent streams.

    Physical Chemistry & Thermochemistry

    This is a collection of problem sets, lecture notes, articles, and labs for physical chemistry, thermochemistry, and thermodynamics.

    Laws of Thermochemistry

    Thermochemical equations are just like other balanced equations except they also specify the heat flow for the reaction. The heat flow is listed to the right of the equation using the symbol ΔH. The most common units are kilojoules, kJ. Here are two thermochemical equations:

    H2 (g) + ½ O2 (g) → H2O (l); ΔH = -285.8 kJ
    HgO (s) → Hg (l) + ½ O2 (g); ΔH = +90.7 kJ

    When you write thermochemical equations, be sure to keep the following points in mind:

    • Coefficients refer to the number of moles. Thus, for the first equation, -282.8 kJ is the ΔH when 1 mol of H2O (l) is formed from 1 mol H2 (g) and ½ mol O2.
    • Enthalpy changes for a phase change, so the enthalpy of a substance depends on whether is it is a solid, liquid, or gas. Be sure to specify the phase of the reactants and products using (s), (l), or (g) and be sure to look up the correct ΔH from heat of formation tables. The symbol (aq) is used for species in water (aqueous) solution.
    • The enthalpy of a substance depends upon temperature. Ideally, you should specify the temperature at which a reaction is carried out. When you look at a table of heats of formation, notice that the temperature of the ΔH is given. For homework problems, and unless otherwise specified, temperature is assumed to be 25°C. In the real world, temperature may different and thermochemical calculations can be more difficult. Certain laws or rules apply when using thermochemical equations:
    • ΔH is directly proportional to the quantity of a substance that reacts or is produced by a reaction.
      Enthalpy is directly proportional to mass. Therefore, if you double the coefficients in an equation, then the value of ΔH is multiplied by two. For example:
      H2 (g) + ½ O2 (g) → H2O (l); ΔH = -285.8 kJ
      2 H2 (g) + O2 (g) → 2 H2O (l); ΔH = -571.6 kJ
    • ΔH for a reaction is equal in magnitude but opposite in sign to ΔH for the reverse reaction.
      For example:
      HgO (s) → Hg (l) + ½ O2 (g); ΔH = +90.7 kJ
      Hg (l) + ½ O2 (l) → HgO (s); ΔH = -90.7 kJ
      This law is commonly applied to phase changes, although it is true when you reverse any thermochemical reaction.
    • ΔH is independent of the number of steps involved.


    This rule is called Hess's Law. It states that ΔH for a reaction is the same whether it occurs in one step or in a series of steps. Another way to look at it is to remember that ΔH is a state property, so it must be independent of the path of a reaction.
    If Reaction (1) + Reaction (2) = Reaction (3), then ΔH3 = ΔH1 + ΔH2

    Amino Acid Structures

    These are the structures for the twenty natural amino acids, plus the general structure for an amino acid.





    Wednesday, November 18, 2009

    Inorganic Chemistry

    If it isn't carbon-based, it's probably covered here. Of course, inorganic reactions of carbon are described, too. You'll find lecture and lab notes, molecular structures, journals, and study guides.


    Types of Inorganic Chemical Reactions

    Elements and compounds react with each other in numerous ways. Memorizing every type of reaction would be challenging and also unncecessary, since nearly every inorganic chemical reaction falls into one or more of four broad categories.

    • Combination Reactions
    Two or more reactants form one product in a combination reaction. An example of a combination reaction is the formation of sulfur dioxide when sulfur is burned in air:
    S (s) + O2 (g) --> SO2 (g)

    • Decomposition Reactions
    In a decomposition reaction, a compound breaks down into two or more substances. Decomposition usually results from electrolysis or heating. An example of a decomposition reaction is the breakdown of mercury (II) oxide into its component elements.
    2HgO (s) + heat --> 2Hg (l) + O2 (g)

    • Single Displacement Reactions
    A single displacement reaction is characterized by an atom or ion of a single compound replacing an atom of another element. An example of a single displacement reaction is the displacement of copper ions in a copper sulfate solution by zinc metal, forming zinc sulfate:
    Zn (s) + CuSO4 (aq) --> Cu (s) + ZnSO4 (aq)
    Single displacement reactions are often subdivided into more specific categories (e.g., redox reactions).

    • Double Displacement Reactions
    Double displacement reactions also may be called metathesis reactions. In this type of reaction, elements from two compounds displace each other to form new compounds. Double displacement reactions may occur when one product is removed from the solution as a gas or precipitate or when two species combine to form a weak electrolyte that remains undissociated in solution. An example of a double displacement reaction occurs when solutions of calcium chloride and silver nitrate are reacted to form insoluble silver chloride in a solution of calcium nitrate.
    CaCl2 (aq) + 2 AgNO3 (aq) --> Ca(NO3)2 (aq) + 2 AgCl (s)
    A neutralization reaction is a specific type of double displacement reaction that occurs when an acid reacts with a base, producing a solution of salt and water. An example of a neutralization reaction is the reaction of hydrochloric acid and sodium hydroxide to form sodium chloride and water:
    HCl (aq) + NaOH (aq) --> NaCl (aq) + H2O (l)
    Remember that reactions can be belong to more than one category. Also, it would be possible to present more specific categories, such as combustion reactions or precipitation reactions. Learning the main categories will help you balance equations and predict the types of compounds formed from a chemical reaction.

    Citric Acid Cycle

    Citric Acid Cycle - Overview of the Citric Acid Cycle



    The Citric Acid Cycle is also known as the Krebs
    Cycle or Tricarboxylic Acid (TCA) Cycle.
    It is a series of chemical reactions that
    takes place in the cell that breaks down
    food molecules into
    carbon dioxide, water, and energy.

    Narayanese, wikipedia.org
    The citric acid cycle, also known as the Krebs cycle or tricarboxylic acid (TCA) cycle, is a series of chemical reactions in the cell that breaks down food molecules into carbon dioxide, water, and energy. In plants and animals, these reactions take place in the mitochondria of the cell as part of cellular respiration. Many bacteria perform the citric acid cycle too, though they do not have mitochondria so the reactions take place in the cytoplasm of bacterial cells. Sir Hans Adolf Krebs, a British biochemist, is credited with discovering the cycle. Sir Krebs outlined the steps of the cycle in 1937.
    The overall reaction for the citric acid cycle is:
    Acetyl-CoA + 3 NAD+ + Q + GDP + Pi + 2 H2O --> CoA-SH + 3 NADH + 3 H+ + QH2 + GTP + 2 CO2
    where Q is ubiquinone and Pi is inorganic phosphate
    In order for food to enter the citric acid cycle, it must be broken into acetyl groups, (CH3CO). At the start of the citric acid cycle, an acetyl group combines with a four-carbon molecule called oxaloacetate to make a six-carbon compound, citric acid. During the cycle, the citric acid molecule is rearranged and stripped of two of its carbon atoms. Carbon dioxide and 4 electrons are released. At the end of the cycle, a molecule of oxaloacetate remains, which can combine with another acetyl group to being the cycle again.
    Substrate --> Products (Enzyme)
    Oxaloacetate + Acetyl CoA + H2O --> Citrate + CoA-SH (citrate synthase)
    Citrate --> cis-Aconitate + H2O (aconitase)
    cis-Aconitate + H2O --> Isocitrate (aconitase)
    Isocitrate + NAD+ Oxalosuccinate + NADH + H + (isocitrate dehydrogenase)
    Oxalosuccinate á-Ketoglutarate + CO2 (isocitrate dehydrogenase)
    α-Ketoglutarate + NAD+ + CoA-SH --> Succinyl-CoA + NADH + H+ + CO2 (α-ketoglutarate dehydrogenase)
    Succinyl-CoA + GDP + Pi --> Succinate + CoA-SH + GTP (succinyl-CoA synthetase)
    Succinate + ubiquinone (Q) --> Fumarate + ubiquinol (QH2) (succinate dehydrogenase)
    Fumarate + H2O --> L-Malate (fumarase)
    L-Malate + NAD+ --> Oxaloacetate + NADH + H+ (malate dehydrogenase)

    Sunday, November 15, 2009

    Chemistry Glossary and Dictionary

    This chemistry glossary offers definitions for terms which are commonly used in chemistry and chemical engineering. An engineering glossary is available, too.







    abrasive
    absolute error
    absolute pressure
    absolute temperature
    absolute uncertainty
    absolute zero
    absorbance
    absorption
    absorption cross section
    absorption spectroscopy
    absorption spectrum
    absorptivity
    accelerator
    accuracy
    acetate
    acid
    acid anhydride
    acid-base titration
    acid dissociation constant - Ka acidic solution
    actinides
    activated complex
    activation energy - Ea actual yield
    addition polymer
    addition reaction
    adhesive
    adsorption
    aerosol
    alchemy
    alcohol
    aldehyde
    alkali metal
    alkaline
    alkaline earth metal
    alkane
    alkene
    alkyl group
    alkyne
    allotrope
    alloy
    alpha particle
    alternating copolymer
    ammeter
    amorphous
    analytical chemistry
    anion
    androgen
    anisotropy
    annealing
    antiferromagnetism
    antioxidant
    aromatic compound
    aqueous solution
    Arrhenius rate equation
    astrochemistry
    atactic
    atom
    atomic mass
    atomic mass unit (amu)
    atomic number
    atomic radius
    atomic weight
    austenite
    autoionization
    Avogadro's Law
    Avogadro's number
    azeotrope

    A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

    Quick Emulsifier Chemistry Demonstration

    Soap is good at cleaning because it acts as an emulsifier, enabling one liquid to disperse into another immiscible liquid. While oil (which attracts dirt) doesn't naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed.
    It's easy to demonstrate the action of an emulsifer. All you need are two immiscible liquids and a little dishwashing detergent or soap.

    Emulsifier Demo Materials

    • water
    • kerosene or oil
    • dishwashing detergent or soap
    • flask or clear glass

    Perform the Demonstration

    1. Add some kerosene or oil together with some water in a flask. Swirl the contents around to try to mix them. What happens?
    2. Add a squirt of dishwashing liquid. Swirl or shake the flask to mix the ingredients. How has the layer of kerosene or oil been changed?

    What could be easier, right?

    Friday, November 13, 2009

    Make Silver Polishing Dip


    As silver oxidizes it will tarnish. This layer of oxidation can be removed without polishing and scrubbing by simply dipping your silver in this non-toxic electrochemical dip. Another big advantage to using a dip is that the liquid can reach places a polishing cloth cannot.
    You can use chemistry to removethe tarnish
    from your silver without even touching it.
    Mel Curtis, Getty Image


    Difficulty: Easy
    Time Required: Minutes

    Here's How:

    1. Line the bottom of the sink or a glass baking dish with a sheet of aluminum foil.
    2. Fill the foil-lined container with steaming hot water.
    3. Add salt (sodium chloride) and baking soda (sodium bicarbonate) to the water. Some recipes call for 2 tsp baking soda and 1 tsp salt, whereas others call for 2 tablespoons each of baking soda and salt. Personally, I wouldn't measure the amounts... just add a bit of each substance.
    4. Drop the silver items into the container so that they are touching each other and resting on the foil. You will be able to watch the tarnish disappear.
    5. Leave heavily tarnished items in the solution for as long as 5 minutes. Otherwise, remove the silver when it appears clean.
    6. Rinse the silver with water and gently buff it dry with a soft towel.
    7. Ideally, you should store your silver in a low-humidity environment. You can place a container of activated charcoal or a piece of chalk in the storage area to minimize future tarnish.

    Tips:

    1. Use care when polishing or dipping silver plated items. It is easy to wear away the thin layer of silver and cause more harm than good through overcleaning.
    2. Minimize exposing your silver to substances which contain sulfur (e.g., mayonnaise, eggs, mustard, onions, latex, wool) as the sulfur will cause corrosion.
    3. Using your silver flatware/holloware or wearing silver jewelry helps to keep it free from tarnish.

    What You Need:

    • Sink or glass pan
    • Hot water
    • Baking soda
    • Salt
    • Aluminum foil
    • Tarnished silv

    Sulfur Pentafluoride: The Color of Love... and Death

    Here's a cute cartoon to brighten your day. Sulfur pentafluoride presumably binds with itself to make disulfur decafluoride, a chemical warfare pulmonary agent similar to your good old friend phosgene. Fun stuff. Disulfur decafluoride eventually decomposes into sulfur hexafluoride (which can be used as a sort of anti-helium in gas density demonstrations) and sulfur tetrafluoride (which reacts with moisture in the air to form sulfurous acid and hydrofluoric acid). Incidentally, while I have no idea about the color of sulfur pentafluoride, I can tell you disulfur decafluoride is colorless and one breath can kill you in a day. It takes a while because its actually the acids produced by the sulfur tetrafluoride reacting with water that likely do you in.

    How to Make Ink - Easy Ink Recipes


    One of my self-improvement projects has been to try to learn how to write legibly. It would be easy to blame my handwriting on being left-handed, but it probably has a lot more to do with trying to write quickly rather than neatly. So, I got a pen and some ink and have been practicing.

    Ink is one of the practical contributions of chemistry. You can make invisible inks and tattoo inks in addition to writing and drawing inks. Although ink recipes may be closely-guarded secrets, the basic principles of preparing ink are simple. You want to mix a pigment with a carrier (usually water). It helps to include a chemical which will allow the ink to flow fluidly and adhere to the paper (gum arabic). Here are some easy ink recipes to get you started ma

    Black Permanent Ink

    • 1/2 tsp lamp black (which you can buy or can make by holding a plate over a candle and collecting the soot or from collecting other char)
    • 1 egg yolk
    • 1 tsp gum arabic
    • 1/2 cup honey
    Mix together the egg yolk, gum arabic, and honey. Stir in the lamp black. This will produce a thick paste which you can store in a sealed container. To use the ink, mix this paste with a small amount of water to achieve the desired consistency.

    Brown Ink

    • 4 teaspoons loose tea or 4-5 teabags
    • 1 teaspoon gum arabic
    • 1/2 cup boiling water
    Pour the boiling water over the tea. Allow the tea to steep for about 15 minutes. Squeeze as much tea (tannin) as possible from the tea or teabags. Stir in the gum arabic. Strain the ink and allow it to cool before bottling it.

    Prussian Blue Ink

    • Prussian Blue pigment (sometimes sold as laundry bluing)
    • water
    Mix the pigment into the water to achieve a rich blue ink.

    Unless you happen to have a calligraphy pen, the easiest way to use these inks is with a homemade quill or a paintbrush. If you have recipes for inks you would like to share, feel free to post them.



    Make an Acid-Base Rainbow Wand

    Here's an easy and colorful chemistry demonstration for you. Take a long glass tube and fill it with Universal Indicator solution. Add a few drops of 0.02M HCl to one end of the tube and seal it with a stopper. Add a couple of drops of 0.02M NaOH to the other end of the tube and seal it. The Universal Indicator will respond to the pH gradient by providing you with a lovely rainbow. You can invert the tube a few times to speed things up.

    You can get a similar result using home chemistry. Fill a clear straw with red cabbage juice. Add a little lemon juice or vinegar to one end of the straw. Add a few drops of baking soda or laundry detergent solution to the other end of the straw.

    On This Day in Science History - November 13

    November 13th is Edward Doisy's birthday. Doisy was an American biochemist who shared the 1943 Nobel Prize in Medicine with Henrik Dam for their work concerning vitamin K. Dam discovered the vitamin and Doisy identified, isolated, determined the structures, and synthesized of two different forms of vitamin K.

    Vitamin K is actually a group of vitamins named after "Koagulations-Vitamin" in German because they are required for processes of blood coagulation. They are also involved in the process of binding calcium during bone metabolism. Deficiency is rare in adults, but newborns have a higher risk, and an injection of vitamin K1 is recommended by the American Academy of Pediatrics shortly after birth. Other research into the K vitamins is looking at links between vitamin K and bone health, Alzheimer's disease, and certain cancers.

    Chemistry Gift Ideas

    Three of my children have birthdays in November, so I've already got a jump on holiday shopping ideas. I have a few different gift lists that I use to jog my memory when I need ideas. Top Science Toys is an all-inclusive collection of fun and educational science toys and gadgets. I also have a list of gifts you can make by applying your command of chemistry.





    This year I've added a new list to the collection: Chemistry Gift Ideas. These are gifts someone with a love of chemistry would especially enjoy. With the possible exception of a chemical volcano, chemistry gifts are a little harder to find in stores than other gifts. Most of the online retailers offer overnight shipping so even if you wait until the last minute for your holiday shopping, you'll still find the perfect present!

    Plasma Ball




    A plasma ball is one of the cool items that made my Top Science Toys list.

    Carbon - Diamond Crystal


    A diamond crystal is a
    form of elemental carbon.
    USGS

    Friday, November 6, 2009

    Oxygen

    Oxygen
    65% of Body Weight
    Oxygen is present in water and other compounds.























    Liquid oxygen in an unsilvered dewar flask.
    Liquid oxygen is blue.
    Warwick Hillier,
    Australia National University, Canberra




    Oxygen is necessary for respiration. You will find this element in the lungs, since about 20% of the air you breathe is oxygen.

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