Question

A chemist determined by measurements that .040 moles of gold participated in a chemical reaction. calculate the mass of gold that participated in the chemical reaction. round your answer to significant digits.

Answer 1

no. moles = the weight / molecular mass

for our cas the molecular mass will be = with the atomic mass

=>

no moles = 0,4

atomic mass = 197 u.a.m.

=> mass of gold = 0,4 * 197 = 78,8 grs.