A metal M forms a compound with the formula MCl3 If the comp

A metal (M) forms a compound with the formula MCl3.

If the compound contains 35.06 % Cl by mass, what is the identity of the metal?

Express your answer as a chemical symbol.

mass of Cl = 35.06 g

moles of Cl = 35.06 / 35.5

= 0.988

MCl3 moles = 1/3 x 0.988 = 0.3292

moles of M = 0.3292

mass of M = 100 -35.06 = 64.94 g

mass / molar mass = moles

64.94 / molar mass = 0.3292

molar mass = 197 g/ mol

molar mass of 197 g / mol metal is gold

so the metal is gold = Au