Ten chemistry questions i'm having a hard time with?

Question

All of the following are Physical properties except for:

Taste

Color

State

Combustion

2: The triple bond in Nitrogen contains two ______ bonds and one _______ bond.

Pi, Sigma

Pi, Psi

Sigma, Psi

Sigma, Pi

3: Substances dissolving in solution are affected by:

Temperature

Concentration

Surface area

All of the above

4: Water is an example of a ______ substance.

Non-polar covalent

Diatomic element

Polar covalent

Electrolytic

5: If a system is at equilibrium, le Chatelier’s principle states that a change in ______ will cause the reaction to reduce the effect in this change.

Number of moles

Temperature

Pressure

All of the above

6: A form of pure oxygen which includes three atoms is:

Ozone

Carbon Trioxide

Air

Carbon Dioxide

7: An example of a one way, irreversible process would be:

A pendulum swinging to one side

A rechargeable battery

An egg falling and breaking

A rubber band stretched to its limit

8: A gain of an electron is known as _____.

Oxidation

Reduction

Electrogainon

Protolosson

9: The Born − Haber process is important for:

Synthesizing Nitrogen

Synthesizing Ammonium

Synthesizing Ammonia

Using up un-needed Hydrogen

10: Most fuels are composed of:

Carbon and Helium

Carbon and Oxygen

Carbon and Hydrogen

Carbon only

Answer 1

1.  Neither taste nor combustion is a physical property.  Taste depends upon reactions between a compound and the taste receptors in your mouth and nose, while combustion is caused when a compound reacts chemically with oxygen or another oxidizer.

2. Two Pi bonds and 1 sigma bond.  Sigma bonds go down the axis of the bond, so there can only be one per bond.

3. All of the above.  Temperature and the concentration already in the solution affect how much will dissolve and the rate of dissolution, while surface area only affects the rate of dissolution.

4. Polar-covalent.  The O atoms have a negative charge, while the H atoms have a positive one, so it is polar.  However, the charges are not separated enough to make it ionic, so it is still covalent.

5. All of the above.  A good way to think about this is by considering that all of these can be products of a reaction - heat can be absorbed or given off, and when gas is produced in a sealed container, pressure will increase...see link

6. Ozone

7. Egg falling and breaking.  Technically, all real processes are irreversible (entropy increases for all real processes, and the total entropy of the universe can never decrease).  Simplistically though, the pendulum will swing back (and can be pushed back), the battery can be drained, and the rubber band can be released.  However, the egg cannot be put back together.  This is an example of the second law of thermodynamics as well.

8. Reduction.  The charge of a positive ion is reduced when more negative electrons are added.

9. Synthesizing ammonia.  Ammonium is an ion that does not exist on its own (ammonia is used to synthesize ammonium salts though).  Nitrogen comprises 70% of air; we don't need to synthesize it.  And excess hydrogen?  That would be really nice, but no.

10. Most fuels used today in transportation are hydrocarbons, which are composed of carbon and hydrogen only.  Helium is inert and is not in any fuels.  Oxygen is present in some fuels, such as ethanol.  It should be noted that coal, a very important fuel, is almost pure carbon.