How many moles (of molecules or formula units) are in each sample? Part A 42.37 g CF2Cl2 Express your answer to four significant figures.

0.3504 mol of CF₂Cl₂.

Explanation:

We need to know the molar mass of CF₂Cl₂ to find out the moles

Molar mass of C = 12 g/mol

Molar mass of F = 19 g/mol

Molar mass of Cl = 35.45 g/mol

Molar mass of CF₂Cl₂ = 12 + 19 . 2 + 35.45 . 2 =120.9 g/mol

Now we determine the moles of our mass

42.37 g . 1 mol / 120.9 g = 0.3504 mol

the complete reaction for the formation of aluminum oxide is as follows;

4al + 3 > 2

so if the molar mass of the is 32.0 g/mol and

so, to form 3.80 mol of

(3.80 mol ) x (3 mol ) x (32.0 g )

dividing by 2 because two moles of will be formed;

∴ 364.8/2   = 182.4g