1.92 g of zinc metal reacts with excess hydrochloric acid to produce hydrogen gas.What volume (L)of hydrogen is generated at STP?

Question

Quizplus · Accepted Answer

To solve this problem, we need to use the molar volume of gas at STP, which is 22.4 L/mol.
First, we need to convert the mass of zinc to moles by dividing by its molar mass:
1.92 g Zn x (1 mol Zn/65.38 g Zn) = 0.0294 mol Zn
According to the balanced chemical equation, 1 mole of Zn produces 1 mole of H2 gas. Therefore, we have 0.0294 mol of H2 gas.
Now we can use the molar volume of gas at STP to find the volume:
0.0294 mol H2 x 22.4 L/mol = 0.656 L H2
Therefore, the final answer is choice letter B, 0.656 L.

192 G of Zinc Metal Reacts with Excess Hydrochloric Acid