given 65g of Zn and 65g of HCl, what is the limiting reactant and reactant in excess in Zn + 2HCl- ZnCl2 + H2
To determine the limiting reactant and the reactant in excess, we need to compare the number of moles of each reactant to the stoichiometric ratio of the balanced chemical equation.
First, calculate the number of moles of each reactant:
The molar mass of zinc (Zn) is 65.38 g/mol. Therefore, the number of moles of Zn can be found using the formula:
moles of Zn = mass of Zn / molar mass of Zn
= 65 g / 65.38 g/mol
= 0.995 mol
The molar mass of hydrochloric acid (HCl) is 36.46 g/mol. Since there are two moles of HCl in the reaction, multiply the molar mass by 2 to find the mass of two moles of HCl:
mass of 2HCl = 2 * molar mass of HCl
= 2 * 36.46 g/mol
= 72.92 g
Now, calculate the number of moles of HCl:
moles of HCl = mass of HCl / mass of 2HCl * (1 mol / molar mass of HCl)
= 65 g / 72.92 g * (1 mol / 36.46 g/mol)
≈ 1.791 mol
According to the balanced chemical equation, the stoichiometric ratio of Zn to HCl is 1:2. This means that for every 1 mole of Zn, 2 moles of HCl are required.
Comparing the number of moles of Zn to HCl, we see that we have an excess of HCl (1.791 mol) compared to Zn (0.995 mol). Therefore, Zn is the limiting reactant and HCl is the reactant in excess.