what is the maximum mass of CFCl2 that can be made from 10g of hydrogen fluoride?

CFCl₂ does not exist. It should be CF₂Cl₂ or CFCl₃ instead.


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Case I : CF₂Cl₂

Molar mass of HF = (1.0 + 19.0) g/mol = 20.0 g/mol
Number of moles of HF reacted = (10 g) / (20.0 g) = 0.5 mol

1 mole of HF can be used to make (1/2) mole of CF₂Cl₂.
Theoretically, number of moles of CF₂Cl₂ can be made = (0.5 mol) × (1/2) = 0.25 mol

Molar mass of CF₂Cl₂ = (12.0 + 19.0×2 + 35.5×2) g/mol = 121 g/mol
Maximum mass of CF₂Cl₂ can be made = (0.25 mol) × (121 g/mol) = 30.3 g


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Case I : CFCl₃

Molar mass of HF = (1.0 + 19.0) g/mol = 20.0 g/mol
Number of moles of HF reacted = (10 g) / (20.0 g) = 0.5 mol

1 mole of HF can be used to make 1 mole of CFCl₃.
Theoretically, number of moles of CFCl₃ can be made = (0.5 mol) × 1 = 0.5 mol

Molar mass of CFCl₃ = (12.0 + 19.0 + 35.5×3) g/mol = 137.5 g/mol
Maximum mass of CFCl₃ can be made = (0.5 mol) × (135.5 g/mol) = 68.8 g

Look up the atomic mass of fluorine (hydrogen is 1), and you can calculate how many moles of HF are in 10 grams, then find the mass of that many moles of CFCl2.