AP Chemistry Exam part 1!?

Question

1. What causes the Hydrogen Bond to form a strong type of intermolecular bond?

a. Hydrogen's high electronegativity.

b. Hydrogen's low electronegativity.

c. The small size of the Hydrogen atom (which allows adjoining molecules to get closer.

d. Hydrogen compounds tend to form ionic bonds

2. Which of the following is a property of a strong acid:

a. It makes a good buffer.

b. It is a weak electrolyte.

c. It has a strong conjugate base.

d. It disassociates in water (becomes strongly ionized)

3. True or False: A buffer inhibits (helps to prevent) changes in pH.

a. True

b. False

4. True or False: pH + pOH = 14

a. True

b. False

5. Chemists believe that chemical reactions occur because the molecules involved in the reaction:____________________________

a. Spontaneously break apart then recombine.

b. Are always unstable.

c. Exist only below a certain minimum temperature.

d. Collide with each other with enough energy to break chemical bonds.

Answer 1

1. I would say...

b. Hydrogen's low electronegativity. (partial positive charge)

2. d. It disassociates in water (becomes strongly ionized)

strong acids dissociate ~100% in water

3. a. True

Buffer helps to prevent large changes in pH when small amounts of strong acid/base are added

4. a. True

As a general rule

5. d. Collide with each other with enough energy to break chemical bonds.

KMT

[Answer: see above]