Can Anyone answer these questions on Temperature/Boiling Point and Bond Order?

Question

Which of the following is a temperature dependent concentration unit?
A. Molarity
B. Mole Fraction
C. Weight Percent
D. Molality
E. None of the above

Ok, so I thought that as you heat a certain solute within water, some of the water molecules will evaporate. But that would create a change in everything won't it?
2. Which of the following molecules has the largest bond order?
A. N2
B. O2
C. Br2
D. S8
I know that you have to do the orbital configuration diagram,but this is a multiple choice question and there has to be an easier way to do it.
Which lists the follwing solutions, 1 molal AgBr,1 molal Br2 and 1 molal LiBr in order of decreasing boiling point?
A. AgBr=LiBr, Br2
B.LiBr,Br2,AgBr
C. Br2,AgBr=LiBr
D.LiBr,AgBr=Br2
E. AgBr,LiBr,Br2
So could someone please tell me the answer and how you arrived at that conclusion? Thanks

Answer 1

I will actually go ahead and tell you that the other two people who answered are wrong about the answer to the first question. The answer is in fact A. Molarity is temperature dependent because it is the number of moles over the volume of solution. As the temperature the volume of solution changes.

As the temp increases molecules speed up and since they have more energy can move further away from the mass of other molecules making the volume of the liquid increase. As they lose energy the molecules stay closer and closer together and lose volume. While the number of moles stay the same. Therefore the correct answer to 1 is A.

Answer 2

1. None of the above.

2. N2 has the largest bond order, a triple bond. O2 is *O=O*, Br2 is single Br-Br, and S8 is a ring of S atoms, all ingly bonded.

3. LiBr has the highest boiling point, because each mole provides two ions, so it's double the molality in ions. AgBr is water-insoluble, so you can't have a 1 molal solution. The boiling point of a bromine solution in water would be partway between the boiling points of the two substances.

Answer 3

e
c
d