OAT OAT: General Chemistry Questions and Answers

Question 1

The rate law for a particular reaction is determined to be: Rate = k[A][B]².
If the concentration of reactant A is doubled and the concentration of reactant B is halved, what will be the effect on the initial rate of the reaction?

Accepted Answer

The rate will be halved.

Answer

The rate will be quadrupled.

Answer

The rate will be doubled.

Answer

The rate will remain the same.

Question 2

During the titration of 25.0 mL of 0.100 M HCl with 0.100 M NaOH, what is the pH of the solution at the equivalence point at 25°C?

Accepted Answer

7.00

Answer

3.00

Answer

5.00

Answer

9.00

Question 3

Which of the following sets of quantum numbers (n, l, m_l, m_s) is NOT permissible for an electron in an atom?

Accepted Answer

(4, 3, -4, +1/2)

Answer

(2, 1, -1, +1/2)

Answer

(3, 2, 0, -1/2)

Answer

(5, 0, 0, +1/2)

Question 4

A chemical reaction is found to have a negative change in enthalpy (ΔH < 0) and a positive change in entropy (ΔS > 0). Which of the following statements is true regarding this reaction?

Accepted Answer

The reaction is spontaneous at all temperatures.

Answer

The reaction is spontaneous only at high temperatures.

Answer

The reaction is spontaneous only at low temperatures.

Answer

The reaction is non-spontaneous at all temperatures.

Question 5

Assuming ideal behavior, which of the following aqueous solutions would be expected to have the lowest freezing point?

Accepted Answer

0.08 m MgCl₂

Answer

0.10 m NaCl

Answer

0.10 m C₆H₁₂O₆ (glucose)

Answer

0.10 m KBr

Question 6

According to the reaction 2 NaN₃(s) → 2 Na(s) + 3 N₂(g), how many liters of nitrogen gas, measured at Standard Temperature and Pressure (STP), are produced from the complete decomposition of 130.0 g of sodium azide (NaN₃)? (Molar mass of NaN₃ = 65.0 g/mol)

Accepted Answer

67.2 L

Answer

22.4 L

Answer

44.8 L

Answer

89.6 L