Chemistry is driving me crazy!?

Question

Okay, I've got thirty problems to do for chemistry, and I've done like 20 of them, and I've literally been working on this since 12 in the afternoon. I've been reading and rereading the chapter, but chemistry doesn't really come easy to me. Biology is my specialty lol. So here are a few problems from the page... could you not only tell me the correct answer, but give me a little explanation as to why.... Your help would be MUCH appreciated. You don't have to answer all of them, just answering one would help me greatly lol.

For 1 and 2 the answer is either hybridization, resonance, or vanderwhaals forces.

Question 1: It is used to explain the fact that the four bonds in methane are equivalent...

Question 2: Its used to explane the fact that the carbon-to-carbon bonds in benzene, C6H6, are identical

Question 3: Which of the following does NOT behave as an electrolyte when it is dissolved in water?

A. CH3OH
B. K2CO3
C. NH4Br
D. HI
E. CH3COONa

...

Question 4: Which of the following statements is always true about the phase diagram of any one-component system?

A. The slope fot he curve representing equilibrium between the vapor and liquid phases is positive.

B. The slope of the curve representing equilibrium between the liquid and solid phases is negative.

C. The slope of the curve representing equilibrium between the liquid and solid phases is positive.

D. The temperature at the triple point is greater than the normal freezing point.

Question 5; The normal boiling point of SO2 is 263.1 K and that of NH3 is 239.7 K. At -40 Celsius what would you predict would happen to the vapor pressure?

A. Ammonia has great VP
B. SO2 has greater VP
C. The VP are equal
D. VP of NH3 is 760 mmHG
E. VP are not predictable from data given.

E. The pressure at the triple point is greater than 1 atmosphere.

Answer 1

1. hybridization - the 4 carbon hydrogen bonds are equivalent, and are hybrids of the of the electron orbital from which they are formed.

2. resonance - You can sort of think of benzene as 1,3,5-cycloheaxatriene, or 2,4,6-cyclohexatriene. The double bonds resonate, or rapidly switch between the carbon atoms. A double bond between two carbon atoms is shorter than a single bond. However, when the carbon carbon bond lengths of benzene are measured, they are all equal.

3. An electrolyte is a solutions of ions. Only methanol, A, does not dissociate in water.

Answer 2

Q1: Obviously the term must involve some aspect of bonding theory. A few hints: resonance occurs when there are alternating multiple and single bonds in a row or in a ring. The four C-H bonds in methane are not in a row. Also remember that van Der Waals forces are INTERmolecular forces.

Q2: Here we have a case of alternating double and single bonds in a six-membered ring. If you draw out the structural formula of benzene, it would appear to have alternating long and short bonds (since double bonds are shorter than single bonds), but apparently this is not the case in reality!

Q3: For these, you will be looking for an ionic bond, usually a metal or pseudo-metal bonded to a non-metal (for example, H+ can sometimes be considered a pseudo-metal cation, but usually only when bonded to a halogen like chloride). An electrolyte is basically a solution of ions, which are charge carriers. So all but one of those will behave as an electrolyte if dissolved in water.

I hope that this will lead you to the right answers.. I don't like just answering other people's homework for them!