Answer to Question #83264 in General Chemistry for Allana Anthony

Question

7.54 Chloral hydrate, a sedative, contains 14.52 % C, 1.83 % H, 64.30 % Cl and 19.35 % O. If it has a molar mass of 165 g, what is the molecular formula?

Answer 1

Answer on Question #83264, Chemistry/ General Chemistry

7.54 Chloral hydrate, a sedative, contains 14.52 % C, 1.83 % H, 64.30 % Cl and 19.35 % O. If it has a molar mass of 165 g, what is the molecular formula?

Solution

1. mass % of C =( mol C * M(C)/ M(sedative)) *100%

14.52 % = (mol C *12.01/ 165) *100%

mol C = 2

2. mass % of H =( mol H * M(H)/ M(sedative)) *100%

1.83 % = (mol H *1.01/ 165) *100%

mol H = 3

3. mass % of Cl =( mol Cl * M(Cl)/ M(sedative)) *100%

64.30 % = (mol Cl *35.45/ 165) *100%

mol Cl = 3

4. mass % of O =( mol O * M(O)/ M(sedative)) *100%

19.35 % = (mol O *16.00/ 165) *100%

mol O = 2

Molecular formula of sedative is C₂H₃Cl₃O₂

Answer: C₂H₃Cl₃O₂