University:
University of California, Berkeley
Course:
CHEM | Chemistry
Academic year:

2023
Views:

89

Pages:

4
Author:

Clint W.

ANSWER KEY You must show all work to receive any credit; and, where applicable, report all numerical answers to the proper number of significant figures. 1. What is the molar mass of CuSO4 * 3H2O? [5 pts.] 213.66 1 mot 2. ' , 3h20 How many grams of magnesium are contained in 212.07 g of MgSO4? [5 pts.] 42.83 3. grams Cusa grams Mg A compound whose molar mass is 92.02 g/mol was analyzed and found to contain 30.45 % N and 69.55 % O. What is the molecular formula of the compound? [15 pts.] 2.17/2.17 4.35/2.17 69.55/16.00 30.45/14.01 46.01 glmol glmol ⇒ 2 = = 92.02 I = = = 2 ⇒ Noz ↳ Nz 04 molecular empirical molar mass formula formula 46.01g / Mol ANSWER KEY You must show all work to receive any credit; and, where applicable, report all numerical answers to the proper number of significant figures. 1. What is the molar mass of Na2CO3 * 10H2O? [5 pts.] 286.19 2. glmol How many grams of oxygen are contained in 212.07 g of CuSO4? [5 pts.] 85.04g 3. A compound whose molar mass is 152.08 g/mol was analyzed and found to contain 63.18 % C, 31.56% O, and 5.26 % H. What is the molecular formula of the compound? [15 pts.] 63.18/12.01 31.56/16.00 5.26/1.01 empirical molecular 2.67 = = = 5.26/1.97 1.97/1.97 5.21/1.97 = = = formula formula C8Hq0z C8HqO3 I × mass = = 3 x 2.64 molar 3 x 3 = = 8 3 7.92 → glmol 152.16 8 ANSWER KEY You must show all work to receive any credit; and, where applicable, report all numerical answers to the proper number of significant figures. 1. What is the molar mass of CaCl2 * 2H2O? [5 pts.] 147.02 2. glmol How many grams of copper are contained in 212.07 g of CuSO4? [5 pts.] 84.43g 3. A compound whose molar mass is 32.05 g/mole was analyzed and found to contain 87.4 % N and 12.6 % H. What is the molecular formula of the compound? [15 pts.] 87.4/14.01 12.6/1.01 I = = = formula empirical 6.24/6.24 12.48/6.24 molar = mass z molecular : : : 16.02 Natty NHZ gland ANSWER KEY You must show all work to receive any credit; and, where applicable, report all numerical answers to the proper number of significant figures. 1. What is the molar mass of CoCl2 * 6H2O? [5 pts.] 237.95 2. How many grams of oxygen are contained in 212.07 g of MgSO4? [5 pts.] 289.9/72.49 4.136/1.38 1.38/1.38 -1111.01 1.39/1.01 342.0ft 72.49 112.76 3. glmol grams A compound whose molar mass is 289.9 g/mol was analyzed and found to contain 49.67 % C, 48.92 % Cl, and 1.39 % H. What is the molecular formula of the compound? [15 pts.] = ↳ 49.67/12.01 = 1.38/1.38 48.92/35.45 =3 I = = = GzCl4H4 I 1135.45) CIH ) = = 4