In the reaction between aluminum and hydrochloric acid, how many moles of hydrogen gas would be liberated when 3.778E-2 grams of aluminum are treated with excess hydrochloric acid?
use molar mass to find moles 3.778E-2 grams of aluminum 26.98 g/mol 0.001400 moles of Al by the equation 2 Al 6 HCl - 2 AlCl3 3 H2 0.001400 moles of Al produces 3/2 's as many moles of H2 0.002100 moles your answer, rounded to 4 sig figs is 0.002100 moles of H2
