Acid–base neutralization reactions Knowledge-Based Practice

Questions

1. 1.

   A 0.420 g sample of an unknown monoprotic acid ($\text{HA}$) requires 35.0 mL of a 0.120 M $\text{NaOH}$ solution to reach complete neutralization. What is the molar mass of the unknown acid?

   • A) 50.0 g/mol
   • B) 75.0 g/mol
   • C) 100 g/mol
   • D) 200 g/mol
2. 2.

   A 25.0 mL sample of a $\text{Ba(OH)}_2$ solution is completely neutralized by 40.0 mL of a 0.150 M $\text{HCl}$ solution. What is the molar concentration of the $\text{Ba(OH)}_2$ solution?

   • A) 0.240 M
   • B) 0.0600 M
   • C) 0.120 M
   • D) 0.480 M
3. 3.

   A mixture is prepared by adding 0.0500 mol of solid $\text{Mg(OH)}_2$ to 250 mL of 0.300 M $\text{HNO}_3$. Assuming complete neutralization occurs, how many moles of which reactant remain unreacted in the mixture?

   • A) $0.0250\text{ mol of Mg(OH)}_2$
   • B) $0.0250\text{ mol of HNO}_3$
   • C) $0.0375\text{ mol of Mg(OH)}_2$
   • D) $0.0125\text{ mol of Mg(OH)}_2$
4. 4.

   What mass of water is produced when 4.90 g of sulfuric acid reacts completely with an excess of sodium hydroxide according to the reaction $\text{H}_2\text{SO}_4(aq) + 2\text{NaOH}(aq) \rightarrow \text{Na}_2\text{SO}_4(aq) + 2\text{H}_2\text{O}(l)$? (Molar masses: $\text{H}_2\text{SO}_4 = 98.1\text{ g/mol}$, $\text{H}_2\text{O} = 18.0\text{ g/mol}$)

   • A) 0.450 g
   • B) 0.900 g
   • C) 3.60 g
   • D) 1.80 g
5. 5.

   What volume of a 0.250 M $\text{Ba(OH)}_2$ solution is required to completely neutralize 30.0 mL of a 0.500 M $\text{H}_3\text{PO}_4$ solution?

   • A) 90.0 mL
   • B) 60.0 mL
   • C) 40.0 mL
   • D) 30.0 mL

Answers and step-by-step solutions appear after you finish the test.