How many liters of hydrogen at STP can be produced by the reaction of 4.15 g of zinc with hydrochloric acid:
Zn + 2HCl -> ZnCl2 + H2
1.42 L
To find the amount of hydrogen gas produced, we need to perform a stoichiometric calculation using the balanced chemical equation:
Zn + 2HCl -> ZnCl2 + H2
First, we need to calculate the number of moles of zinc (Zn) using its molar mass.
Molar mass of Zn = 65.38 g/mol
Number of moles of Zn = mass / molar mass
Number of moles of Zn = 4.15 g / 65.38 g/mol
Number of moles of Zn = 0.0634 mol
According to the stoichiometry of the balanced equation, 1 mole of zinc reacts with 2 moles of HCl to produce 1 mole of hydrogen gas (H2).
Therefore, the number of moles of H2 produced will also be 0.0634 mol.
At standard temperature and pressure (STP), 1 mole of any ideal gas occupies 22.4 liters of volume.
So, the volume of hydrogen gas produced will be:
Volume of H2 = number of moles of H2 * molar volume at STP
Volume of H2 = 0.0634 mol * 22.4 L/mol
Volume of H2 = 1.42 liters
Therefore, 1.42 liters of hydrogen gas can be produced by the reaction of 4.15 g of zinc with hydrochloric acid.