Module 5 Unit 1 Assignment A - MODULE 5 UNIT 1 Assignment Part A 1 Calculate the number of moles for each of the following cases(10 points a 1.85 g of

# Module 5 Unit 1 Assignment A - MODULE 5 UNIT 1 Assignment...

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MODULE 5 UNIT 1 Assignment Part A 1. Calculate the number of moles for each of the following cases: (10 points) a) 1.85 g of potassium chloride, KCl K :39.10 + Cl :35.45 = 74.55g/mol. x 1.85g = 137.92 moles = 1.38 x 10 2 moles b) 2.50 kg of sodium sulphide, Na 2 S Na : 22.99 (x2) + S: 32.06 = 78.04g/mol. 2.50kg/0.07804 = 32.03 moles = 3.20 x 10 1 moles c) 3.5 g of calcium nitrate, Ca(NO 3 ) 2 Ca: 48.08 + N:14.01 (x2) O: 16.00 (x6) = 172.10g/mol. X 3.5g = 602.35 = 6.02 x 10 2 d) 0.345 g of ammonium phosphate, (NH 4 ) 3 PO 4 N:14.01 (x3 = 42.03) + H:1.01 (x12 = 12.12) + P:30.98 + O:16.00 (x4 = 64) = 149.13g/mol. X 0.345g = 51.45 moles = 5.15 x 10 1 moles e) 34 g of C 7 H 8 Cl 4 a PCB (polychlorinated biphenyl) C: 12.01 (x7= 84.07) + H: 1.01 (x8= 8.08) + Cl:35.45 (x4= 141.80) = 233.95g/mol. X34g = 7954.3 = 7.95 x 10 3 2. Two full bottles contain respectively 1.0 kg of potassium nitrate, KNO 3 , and 1.0 kg of strontium chloride, SrCl 2 . Which bottle contains the greater number of moles? How many more moles does it contain? (6 points) K : 39.10 + N : 14.01 + O : 16.00 (x3= 48) = 101.11g/mol. 1000/101.11 = 9.89 moles Sr : 87.62 + Cl : 35.45 (x2=70.90) = 158.52g/mol. 1000/158.52 = 6.30 moles The bottle with the 1.0 kg of potassium nitrate has 3.59 moles more than the strontium chloride bottle as the potassium nitrate has 9.89 moles compared to the bottle of strontium chloride which has 6.30 moles.
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