How many liters of h2 gas can be produced at 0? c and 1.00 atm (stp) from 42.0 g of zn? zn (s) + 2hcl (aq) ? zncl2 (aq) + h2 (g) ?

The chemical reaction would be:

Zn (s) + 2HCl (aq) = ZnCl2 (aq) + H2 (g)

At STP 1 mol of an ideal gas is equa to 22.4 L of the gas. We need to assume that H2 produced is an ideal gas. We can calculate as follows:

42.0 g Zn (1 mol / 65.38 g) (1 mol H2 / 1 mol Zn) (22.4 L / 1 mol) = 14.39 L H2 produced