MCAT General Chemistry Question 191: Answer and Explanation

Home > MCAT Test > MCAT general chemistry practice tests

Test Information

Use your browser's back button to return to your test results.
Do more MCAT general chemistry practice tests.

Question: 191

2. The K_sp of NaCl in water is 35.9 at 25°C. If 500 mL of 12 M NaOH(aq) and 500 mL of 12 M HCl(aq) solution both at 25°C are combined, what would best describe the resulting solution?

A. I only
B. III only
C. I and II
D. I and III

Correct Answer: A

Explanation:

A In order to participate in intermolecular hydrogen bonding, a molecule must be able to act as both a hydrogen bond donor and acceptor. In order to act as a hydrogen bond donor, a molecule must possess a hydrogen (H) atom covalently bound to a nitrogen (N), oxygen (O), or fluorine (F) atom. In order to act as a hydrogen bond acceptor, a molecule must have an oxygen, nitrogen, or fluorine atom with an unshared pair of electrons. CH₃CO₂H meets both of these requirements, and is therefore a valid choice. CO₂ does not possess any hydrogen atoms and is therefore an invalid option. While H₂S may seem like an enticing choice, sulfur is not sufficiently electronegative to produce hydrogen bonding when covalently bound to hydrogen atoms.

Previous Next