Final answer:
The amount of hydrogen gas produced from 0.6 mole of hydrochloric acid reacting with excess zinc is 0.3 moles, following the 2:1 stoichiometric ratio of HCl to H₂ from the balanced equation.
Step-by-step explanation:
The amount of hydrogen gas produced when 0.6 mole of hydrochloric acid reacts with excess zinc can be found by looking at the stoichiometry of the balanced chemical equation for the reaction:
Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g)
From the equation, it's clear that 1 mole of Zn reacts with 2 moles of HCl to produce 1 mole of H₂. Therefore, if 0.6 mole of HCl is used, half that amount, or 0.3 moles of H₂, would be produced because HCl is in a 2:1 ratio with H₂. Thus, the correct answer is A. 0.3 moles.