Chemistry Engineering Interview Preparation Guide

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Any chemical species that has a tendency to accept electrons and thereby undergoing reduction themselves is known as an oxidizing agent

There are multiple forms of the molecule "chlorooctane." This is because the chlorine atom can be attached to the octane chain in several different places, and each different placement will result in a different dipole moment. If you specify the structure of the compound more precisely (1-chlorooctane or 2-chlorooctane for example), it is possible to determine its dipole moment.

You cannot extract ephedrine or pseudo ephedrine from a mineral block. Anyone who tells you that they have done it is either mistaken or a liar.

Hydrocarbons are compounds made entirely out of Hydrogen and Carbon.

Exactly how you prepare will depend on what you are starting with. Typically, to make a 1 M HCl solution, you will be starting with a stock solution of more concentrated HCl that you will then dilute.

KOH is potassium hydroxide, which is a strong base. HCl is hydrochloric acid, which is a strong acid.

► Of, relating to, or derived from living organisms: organic matter.
► Of, relating to, or affecting a bodily organ: an organic disease.

In addition, DNA would chemically be considered organic since it contains carbon as the primary chemical backbone of the molecule.

Hydra is a type of polyp. It is an animal, because it moves around like one even though it looks like a plant. A hydra is from the Phylum Cnidarian and belongs with others such as jellyfish and coral.

Alum is a chemical (aluminum potassium sulphate); it tends to be whitish powder with several uses, including:

1. As an astringent
2. As an antibacterial
3. As a food preservative
4. As a 'Styptic pencil' to heal shaving cuts
5. To stem the flow of minor blood loss and cuts
6. Soaked into materials to make them flame retardant

There are other uses, but these are some of the more common ones.

Both laws have to do with relating to Dalton's Atomic Theory. The only difference is that the Law of Definite Proportions deals with elements combining to form ONE compound in a simple whole number ratio. The Law of Multiple Proportions is comparing the same 2 elements that make up 2 different compounds the division of these 2 ratios should equal a simple whole number ratio.

For example, Carbon and oxygen can combine to form carbon monoxide and carbon dioxide. If you calculated each compounds ration of oxygen to carbon, you would get the following ratios: compound A would equal a combining ratio of 1.34:1 (O:C). Compound B would equal a combining ratio of 2.67:1 (O:C).

If you divided the bigger ratio by the smaller ratio you would have that oxygen combines with a ratio of 2.67/1.34, which would equal 1.99:1, which is close enough to 2:1.

A molecule of DNA is double-stranded. The molecule has the shape of a double helix.

The DNA molecule consists of two complementary strands oriented in an anti-parallel fashion. Each strand is composed of nucleotides. A nucleotide consists of a base (a purine or pyrimidine), a sugar (between the other two components) named deoxyribose, and a phosphate group. Nucleotides are linked to each other via phosphodiester bonds, forming a sugar-phosphate backbone to each strand.

The base of each nucleotide projects into the interior cavity of the helix. Each base is opposite another base: adenine (a purine) is always paired with thymine (a pyrimidine), and guanine (purine) with cytosine (pyrimidine); this phenomenon is called complementary base pairing.

Each nucleotide forms hydrogen bonds with its complementary base on the other strand. Two hydrogen bonds form between adenine and thymine; three hydrogen bonds form between guanine and cytosine.

A medicine dropper is an instrument used to measure small amount of liquids, usually in milligrams. You will first pinch the handle before you submerge it in the water.

There are 30 electrons in benzene. This includes 24 carbon electrons and 6 hydrogen electrons. There are 12 electrons shared between C and H, and 18 between C and C. (6 electrons in up ring, 6 in down ring and 6 between C and C).

Dipole moment is the measure polarity of a polar covalent bond. It is defined as the product magnitude of charge on the atoms and the distance between the two bonded atoms. Its common unit is debye and SI unit is columb meter.

Tin is obtained in various places tin is found mainly in the ore cassiterite, which is found in Malaysia, Bolivia, Thailand, and Nigeria.

Organic chemistry is the chemistry of carbon compounds while inorganic chemistry is the chemistry of all the rest of the elements on the periodic table.

Trimethylindium is extremely reactive towards oxygen and water. With low concentrations of oxygen (ppb to ppm to a few %), it immediately forms dimethylindium methoxide (Me2InOMe) as the first reaction product by insertion of O between In and C. With increased concentrations of oxygen (several %, atmospheric air or pure oxygen), it burns or explodes. Similar insertion reactions are expected with other elements of Group 16 (such as S, Se and Te) with highly vigorous outburst at higher concentrations of S, Se and Te.

Trimethylindium reacts readily and vigorously with water to form Me2InOH and Methane (CH4) gas if the concentration of H2O is very small (up to 1000's ppm). With high concentrations of water (% level), trimethylindium can burn and often explode leaving behind In (OH)3, In2O3 as the final products. Extremely violent reactions of trimethylindium are also known with oxidizers. Such as H2O2, KMnO4, HNO3, Bleach) and halogenated compounds (CCl4, CBrCl3, CBr2Cl2, CHCl3, C2Cl6, and halocarbon oils).

It is more expensive and you have less of a variety to choose. Stores like Wegamans have a variety of organic food though.

Since organic produce does not contain chemicals and stabilizers, it spoils more quickly. It also may appear "uglier" (asymmetrical, not shiny or waxy, dirty).

► First, remember definition of M (moles), M = moles of species / L.

0.33 M = 0.33 moles HCl / L

► Then, multiple your volume by the molar concentration:

0.33 moles HCl / L x 0.70 L = 0.231 moles HCl

It is helpful to carry the units with your calculations. That way you can check that numerators and denominators cancel to give you the units of your answer.

1) Light energy

2) == 6CO2 + 6H2O --------> C6H12O6 + 6O2 ==

3) Carbon dioxide + water +light energy------> carbohydrates+ oxygen

A tripod is a general term for a stand or support with three legs. It is often used to support a camera gun, or to place above the Bunsen burner in the science lab to heat/boil anything.

In the science laboratory, metal gauze is placed on top of it to give support to the beaker (An iron ring clamp with a ring stand can often be used instead and an iron ring allows for easy height adjustment).

Ciprofloxacin is used to fight bacterial infections. I am currently taking this medicine to help cure mastoiditis.

Protein is a source of backup energy that your body stores, a large complex molecule made up of one or more chains of amino acids. Proteins perform a wide variety of activities in the cell.

Highly complex nitrogenous compounds found in all animal and vegetable tissues. Proteins, the principal constituents of the protoplasm of all cells (apart from water), are of high molecular weight, and consist essentially of combinations of amino acids in peptide linkages. Twenty different amino acids are commonly found in proteins and each protein has a unique, genetically defined amino acid sequence that determines its specific shape and function.

(FeAsS) Arsenopyrite also known as mispickel is the most common mineral containing arsenic.

An explosion is nothing more than the rapid release of energy. This is most commonly due to the rapid combustion of a material, although nuclear explosions do not involve combustion. The combustion of any hydrocarbon or other carbon-containing substance ALWAYS produces carbon dioxide. This might include explosion due to a natural gas or gasoline.

It is possible, however, to explode substances that do not contain carbon, such as pure hydrogen (the very famous Hindenburg disaster in 1937 is a classic example of a very big hydrogen gas explosion. An explosion of hydrogen produces only water vapor (H2O), NOT carbon dioxide (CO2).

Also, nuclear explosions (both fusion and fission) themselves do not produce carbon dioxide, although they may cause surrounding objects to incinerate, which would release carbon dioxide.