Acid–base neutralization reactions Original Scenario-Based Download PDF

Questions

1. 1.

   In the atmospheric purification vault of a floating aerostat city, an emergency chamber neutralizes a spill containing 0.60 mol of barium hydroxide, $\text{Ba(OH)}_2$, using 0.80 mol of nitric acid, $\text{HNO}_3$, according to the balanced equation $\text{Ba(OH)}_2\text{(aq)} + 2\text{HNO}_3\text{(aq)} \rightarrow \text{Ba(NO}_3\text{)}_2\text{(aq)} + 2\text{H}_2\text{O(l)}$. If the neutralization reaction proceeds to completion, what is the mass of water produced? (Molar mass of $\text{H}_2\text{O} = 18.0\text{ g/mol}$)

   • A) 14.4 g
   • B) 21.6 g
   • C) 7.2 g
   • D) 25.2 g
2. 2.

   During a deep-space crystallization mission, a science probe neutralizes 0.15 mol of phosphoric acid according to the equation $\text{H}_3\text{PO}_4\text{(aq)} + 3\text{NaOH(aq)} \rightarrow \text{Na}_3\text{PO}_4\text{(aq)} + 3\text{H}_2\text{O(l)}$. If the reaction proceeds to completion with a stoichiometric amount of sodium hydroxide, what mass of trisodium phosphate salt is produced? (Molar masses: $\text{Na} = 23.0\text{ g/mol}$, $\text{P} = 31.0\text{ g/mol}$, $\text{O} = 16.0\text{ g/mol}$)

   • A) 8.2 g
   • B) 24.6 g
   • C) 49.2 g
   • D) 73.8 g
3. 3.

   In a subterranean orbital outpost, a bioreactor generates 400 mL of an uncalibrated hydrochloric acid ($\text{HCl}$) coolant wash that must be treated before recycling. An automated reclamation unit completely neutralizes the wash by dispensing exactly 0.30 mol of solid calcium hydroxide ($\text{Ca(OH)}_2$) according to the equation $2\text{HCl(aq)} + \text{Ca(OH)}_2\text{(s)} \rightarrow \text{CaCl}_2\text{(aq)} + 2\text{H}_2\text{O(l)}$. What was the initial molar concentration of the hydrochloric acid solution?

   • A) 0.75 M
   • B) 1.50 M
   • C) 0.375 M
   • D) 3.00 M
4. 4.

   A terraforming atmospheric drone on an arid exoplanet collects 150 mL of 0.40 M sulfuric acid from an active volcanic vent. To prevent equipment corrosion, the drone neutralizes the sample using a 0.50 M potassium hydroxide solution according to the balanced equation $\text{H}_2\text{SO}_4\text{(aq)} + 2\text{KOH(aq)} \rightarrow \text{K}_2\text{SO}_4\text{(aq)} + 2\text{H}_2\text{O(l)}$. What volume of the potassium hydroxide solution must be added to achieve complete neutralization?

   • A) 60 mL
   • B) 120 mL
   • C) 240 mL
   • D) 300 mL
5. 5.

   Inside the hydroponic bay of an exploratory deep-sea habitat, an automated pipe breach releases 0.25 mol of sulfuric acid ($\text{H}_2\text{SO}_4$) into a closed treatment basin. The environmental computer initiates an emergency neutralization protocol that injects solid sodium hydroxide ($\text{NaOH}$) according to the reaction $\text{H}_2\text{SO}_4\text{(aq)} + 2\text{NaOH(s)} \rightarrow \text{Na}_2\text{SO}_4\text{(aq)} + 2\text{H}_2\text{O(l)}$. Given molar masses of 23.0 g/mol for Na, 16.0 g/mol for O, and 1.0 g/mol for H, what mass of sodium hydroxide must be dispensed to completely neutralize the acid?

   • A) 10.0 g
   • B) 40.0 g
   • C) 80.0 g
   • D) 20.0 g