STEM A_Pre-Final Exam

SURNAME, FIRST NAME, M.I.

SECTION

• A

• B

• C

Which of the following is a spontaneous process?

• A ball rolls up a hill

• A fruit turns yellow as it ripens

• Throwing 50 coins results in all tails

• Ice is formed at ambient temperature

The second law of thermodynamics states that .

• ΔH° = Σ n ΔHf° (products) – Σ m ΔHf° (reactants).

• ΔS = qrev/T at constant temperature.

• for any spontaneous process, the entropy of the universe increases.

• the entropy of a pure crystalline substance at absolute zero is zero.

A reaction that is spontaneous .

• is very rapid

• will proceed without outside intervention

• is also spontaneous in the reverse direction

• has an equilibrium position that lies far to the left

The entropy will usually increase when:

I. a molecule is broken into two or more smaller molecules.

II. a reaction occurs resulting in an increase in the number of moles of gas.

III. a solid change to a liquid.

IV. a liquid change to a gas.

• I, II, III only

• II and III only

• I only

• I, II, III, and IV

Based on Brønsted-Lowry theory, which of the following are acid-base reactions?

• NaCl → Na+ + Cl-

• HF + H2 → F- + H3O+

• MgO + HCl → MgCl2 + H2

• NaOH + HCl → NaCl + H2O

Which best describes the difference between a base and its conjugate acid?

• The base has an additional H⁺ ion.

• The base has an additional OH^- ion.

• The conjugate acid has an additional H⁺ ion.

• The conjugate acid has an additional OH^- ion

Which household product contains a common based of sodium hydroxide?

• Bleach

• Vinegar

• Ammonia

• Drain Cleaner

The thermodynamic quantity that expresses the degree of disorder in a system is .

• enthalpy

• internal energy

• heat flow

• entropy