2HCl(aq) + Zn(s) → ZnCl2(aq) + H2(g)
The molar mass of hydrogen (H) is 1 g/mol, the molar mass of chlorine (Cl) is 35 g/mol, and the molar mass of zinc (Zn) is 65 g/mol. When 130 grams of zinc react completely in hydrochloric acid (HCl), how much is the total mass of the products?
(1 point)
Responses
270 g
270 g
130 g
130 g
144 g
144 g
274 g
274 g
First, we need to calculate the molar mass of ZnCl2:
Molar mass of ZnCl2 = 65 g/mol (Zn) + 2(35 g/mol) (Cl) = 65 g/mol + 70 g/mol = 135 g/mol
Next, we need to determine the amount of ZnCl2 produced by the reaction:
Moles of Zn = 130 g / 65 g/mol = 2 moles
According to the reaction, 1 mole of Zn produces 1 mole of ZnCl2, so 2 moles of Zn produce 2 moles of ZnCl2.
Total mass of ZnCl2 = 2 moles x 135 g/mol = 270 g
Finally, we calculate the total mass of the products:
Total mass = mass of ZnCl2 (270 g) + mass of H2 (molar mass of H2 x moles of H2)
Molar mass of H2 = 2 g/mol
Moles of H2 = 2 moles (from the reaction)
Mass of H2 = 2 moles x 2 g/mol = 4 g
Total mass = 270 g (ZnCl2) + 4 g (H2) = 274 g.