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Friday, October 30, 2009

Nobel Prize

Nobel Prize is the greatest honorable prize in the world. The prize was started since 1901 as per famous Swedish scientist and dynamite inventor Alfred Nobel's will and his property.

1. How many categories are Awarded Nobel Prize? Ans: 6. Physics, Chemistry, Medicine, Literature, Economics & Peace.
2. How many institutes is Awarded Nobel Prize? Ans: 4
3. Which institute is Awarded Nobel Prize in Medicine? Ans: Karolinska Institute, Sweden.
4. Which institute is Awarded Nobel Prize in Literature? Ans: Swedish Academy.
5. Which institute is Awarded Nobel Prize in Physics, Chemistry & Economics? Ans: Royal Swedish Academy of Sciences.
6. Which institute is Awarded Nobel Prize in Peace? Ans: Nobel Committee of Norwegian Parliament, Norway.
7. How many people could maximum awarded in one category? Ans: 3 People.
8. Which category Nobel Prize could awarded both person and institute? Ans: Nobel Peace Award.
9. Did not consider for Nobel Prize? Ans: Any dead person.
10. Though as per above rule who have awarded Nobel Prize after death? Ans: Swedish poet 'Erik Axel Karlfeldt' (1931) and NU Secretary General 'Dag Hammarskjöld' (1961).
11. When was started Nobel award in Economics? Ans: 1969.
12. Which Nobel Prize traditionally awarded on Thursday? Ans: Literature.
13. Who was the first Nobel Prize winner in Asia? Ans: 'Le Duc Tho', Vietnam, But he had refused it.
14. Who was the first Nobel Prize winner as a Muslim? Ans: Anwar El-Sadat, Egypt (1978).
15. Who was at first Won Nobel Prize Twice? Ans: Maria Curie (1903 & 1911).
16. Who was the first Nobel Prize winner USA President? Ans: Theodore Roosevelt (1906).
17. Who was the first Nobel Prize winner as Asian in Economics? Ans: Amartya Sen, India (1998).
18. Who was the first Nobel Prize winner as Muslim in Literature? Ans: Naguib Mahfouz, Egypt (1988).
19. Who was the first & only Nobel Prize winner as Muslim in Physics? Ans: Abdus Salam, Pakistan (1979).
20. Who was the first & only Nobel Prize winner as Muslim in Chemistry? Ans: Ahmed Zewail, Egypt (1999).
21. Who was the first Nobel Prize winner as Asian in Physiology or Medicine? Ans: Har Gobind Khorana, India (1929).
22. Who was the first Nobel Prize winner in women? Ans: Maria Curie, France (1903).

Wednesday, October 28, 2009

What Is Radioactivity? What is Radiation?

Question: What Is Radioactivity? What is Radiation?


Unstable atomic nuclei will spontaneously decompose to form nuclei with a higher stability. The decomposition process is called radioactivity. The energy and particles which are released during the decomposition process are called radiation. When unstable nuclei decompose in nature, the process is referred to as natural radioactivity. When the unstable nuclei are prepared in the laboratory, the decomposition is called induced radioactivity.

Answer: There are three major types of natural radioactivity:


Alpha Radiation
Alpha radiation consists of a stream of positively charged particles, called alpha particles, which have an atomic mass of 4 and a charge of +2 (a helium nucleus). When an alpha particle is ejected from a nucleus, the mass number of the nucleus decreases by four units and the atomic number decreases by two units. For example:
23892U -> 42He + 23490Th
The helium nucleus is the alpha particle









This trefoil is the hazard
symbol for radioactive material.



Beta Radiation
Beta radiation is a stream of electrons, called beta particles. When a beta particle is ejected, a neutron in the nucleus is converted to a proton, so the mass number of the nucleus is unchanged, but the atomic number increases by one unit. For example:
23490 -> 0-1e + 23491Pa
The electron is the beta particle.


Gamma Radiation
Gamma rays are high-energy photons with a very short wavelength (0.0005 to 0.1 nm). The emission of gamma radiation results from an energy change within the atomic nucleus. Gamma emission changes neither the atomic number nor the atomic mass. Alpha and beta emission are often accompanied by gamma emission, as an excited nucleus drops to a lower and more stable energy state.
Alpha, beta, and gamma radiation also accompany induced radioactivity. Radioactive isotopes are prepared in the lab using bombardment reactions to convert a stable nucleus into one which is radioactive. Positron (particle with the same mass as an electron, but a charge of +1 instead of -1) emission isn't observed in natural radioactivity, but it is a common mode of decay in induced radioactivity. Bombardment reactions can be used to produce very heavy elements, including many which don't occur in nature.

Solutions, Suspensions, Colloids, and Dispersions

Solutions
A solution is a homogeneous mixture of two or more components. The dissolving agent is the solvent. The substance which is dissolved is the solute. The components of a solution are atoms, ions, or molecules, which makes them 10-9 m or smaller in diameter.
Example: Sugar and Water

Suspensions
The particles in suspensions are larger than those found in solutions. Components of a suspension can be evenly distributed by a mechanical means, like by shaking the contents, but the components will settle out.
Example: Oil and Water

Colloids
Particles intermediate in size between those found in solutions and suspensions can be mixed such that they remain evenly distributed without settling out. These particles range in size from 10-8 to 10-6 m in size and are termed colloidal particles or colloids. The mixture they form is called a colloidal dispersion. A colloidal dispersion consists of colloids in a dispersing medium.
Example: Milk

More Dispersions
Liquids, solids, and gases all may be mixed to form colloidal dispersions.
Aerosols: solid or liquid particles in a gas.Examples: Smoke is a solid in a gas. Fog is a liquid in a gas. Bold

Sols: solid particles in a liquid.Example: Milk of Magnesia is a sol with solid magnesium hydroxide in water.
Emulsions: liquid particles in liquid.Example: Mayonnaise is oil in water.

Gels: liquids in solid.Examples: gelatin is protein in water. Quicksand is sand in water.

Telling Them Apart
You can tell suspensions from colloids and solutions because the components of suspensions will eventually separate. Colloids can be distinguished from solutions using the Tyndall effect. A beam of light passing through a true solution, such as air, is not visible. Light passing through a colloidal dispersion, such as smoky or foggy air, will be reflected by the larger particles and the light beam will be visible

Tuesday, October 27, 2009

Van der Waals Bond Definition

Definition: A van der Waals bond is a secondary interatomic bond between adjacent molecular dipoles. A van der Waals bond may be permanent or induced.

Hydrogen Bond Definition - Chemistry Glossary Definition of Hydrogen Bond
Definition: A hydrogen bond is a type of attractive (dipole-dipole) interaction between an electronegative atom and a hydrogen atom bonded to another electronegative atom. This bond always involves a hydrogen atom. Hydrogen bonds can occur between molecules or within parts of a single molecule. A hydrogen bond tends to be stronger than van der Waals forces, but weaker than covalent bonds or ionic bonds.




This is a basic diagram
of an atom, with protons,
neutrons and electrons labeled.



Atom Definition: An atom is the defining structure of an element, which cannot be broken by any chemical means. A typical atom consists of a nucleus of protons and neutrons with electrons circling this nucleus.

Atom Examples: hydrogen, carbon-14, zinc, cesium, Cl- (a substance can be an atom and an isotope or ion at the same time)

Monday, October 26, 2009

Adenosine Monophosphate (AMP)




Adenosine monophosphate (AMP) is also known as 5'-adenylic acid. AMP is one of the nucleotides found in RNA.


Mysid, wikipedia.org



The molecular formula for adenosine monophosphate (AMP) is C10H14N5O7P.





Adenosine Triphosphate (ATP)


Adenosine 5'-triphosphate (ATP) is a nucleotide that is used to supply energy within cells.


wikipedia commons

Molecular Structures

Acetone



Adipic Acid






Cloud in a Bottle Demonstration(Use Smoke to Form a Cloud)

Here's a quick and easy science project you can do: make a cloud inside a bottle. Clouds form when water vapor forms tiny visible droplets. This results from cooling the vapor. It helps to provide particles around which the water can liquefy. In this project, we'll use smoke to help form a cloud.









You can make your own
cloud in a bottle using a bottle,
some warm water, and a match.
Anne Helmenstine




Cloud in a Bottle Materials

Let's Make Clouds

  1. Pour just enough warm water in the bottle to cover the bottom of the container.
  2. Light the match and place the match head inside the bottle.
  3. Allow the bottle to fill with smoke.
  4. Cap the bottle.
  5. Squeeze the bottle really hard a few times. When you release the bottle, you should see the cloud form. It may disappear between 'squeezes'

The Other Way to Do It

Ok, here's the ideal gas law:

PV = nRT, where P is pressure, V is volume, n is number of moles, R is a constant, and T is temperature.


If we're not changing the amount of gas (as in a closed container) then if you raise the pressure, the only way for the temperature of the gas to be unchanged is by decreasing the container volume proportionally. I wasn't sure I could squeeze the bottle hard enough to achieve this (or that it would bounce back) and I wanted a really dense cloud for the photograph so I did the not-as-child-friendly version of this demonstration (still pretty safe). I poured water from my coffeemaker into the bottom of the bottle. Instant cloud! (... and a slight melting of the plastic) I couldn't find any matches, so I lit a strip of cardboard on fire, inserted it into the bottle, and let the bottle get nice and smoky (and melted more plastic... you can see the deformation in the photo). Dense cloud, no squeezing required, though of course it still worked.

How Clouds Form
Molecules of water vapor will bounce around like molecules of other gases unless you give them a reason to stick together. Cooling the vapor slows the molecules down, so they have less kinetic energy and more time to interact with each other. How do you cool the vapor? When you squeeze the bottle, you compress the gas and increase its temperature. Releasing the container lets the gas expand, which causes its temperature to go down. Real clouds form as warm air rises. As air gets higher, its pressure is reduced. The air expands, which causes it to cool. As it cools below the dew point, water vapor forms the droplets we see as clouds. Smoke acts the same in the atmosphere as it does in the bottle. Other nucleation particles include dust, pollution, dirt, and even bacteria.

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