OAT General Chemistry 2

Question 1

Which quantum number describes the shape of an atomic orbital?

Accepted Answer

Angular momentum quantum number (l)

Answer

The angular momentum quantum number (l) determines the shape of the orbital (s, p, d, f).

Question 2

A buffer solution is BEST described as one that:

Accepted Answer

Resists changes in pH upon addition of small amounts of acid or base

Answer

A buffer resists pH changes by containing a weak acid and its conjugate base (or weak base and conjugate acid).

Question 3

What is the oxidation state of sulfur in H2SO4?

Accepted Answer

+6

Answer

In H2SO4, hydrogen is +1 and oxygen is -2, so sulfur must be +6 to balance the neutral molecule.

Question 4

According to VSEPR theory, what is the molecular geometry of SF4?

Accepted Answer

See-saw

Answer

SF4 has 4 bonding pairs and 1 lone pair on sulfur, giving it a see-saw (seesaw) geometry.

Question 5

Which of the following has the highest boiling point?

Accepted Answer

NH3

Answer

NH3 has the highest boiling point due to strong intermolecular hydrogen bonding.

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