pg 335 34. Determine the molar mass of each ionic compound. NaOH CaCl2 KC2H3O2 c) a) 22.99g Na 1 mol Na 39.10g K 1 mol K 1 mol Na* =22.99g Na 1 mol K* = 39.10g K 16.00g O 1 mol O 2 mol C* 12.01g C 1 mol C 1 mol O* =16.00g O = 24.02 C 1.008g H 1 mol H 1 mol H* =1.008g H 1.008g H 1 mol H 3 mol H* = 3.024g H Molar mass=40.08 g/mol b) 40.08g Ca 1 mol Ca = 40.08 g Ca 16.00g O 1 mol O 1 mol Ca* 2 mol O* = 32.00 O 35.45g Cl 1 mol Cl Molar mass= 98.14 g/mol 2 mol Cl* =70.90 g Cl Molar mass= 110.98 g/mol

pg 335 35. Calculate the molar mass of each molecular compound. C2H5OH HCN CCl4 a) 2 𝑚𝑜𝑙 𝐶 𝑥 12.01 𝑔 𝐶 1 𝑚𝑜𝑙 𝐶 6 𝑚𝑜𝑙 𝐻 𝑥 1.008 𝑔 𝐻 1 𝑚𝑜𝑙 𝐻 1 𝑚𝑜𝑙 𝑂 𝑥 16.00 𝑔 𝑂 1 𝑚𝑜𝑙 𝑂 = 24.0 g/mol b) 1.008g H 1 mol H 1 mol H* =1.008g H = 6.0 g/mol 12.01g C 1 mol C 1 mol C* = 12.01g C = 16.0 g/mol 14.01g N 1 mol N 1 mol N* = 14.01g Molar mass = 46.0 g/mol c) 12.01g C 1 mol C 1 mol* =12.01 g C Molar mass HCl=27.03 g/mol 35.45g Cl 1 mol Cl 4 mol Cl* = 141.80 g Cl Molar mass CCl4= 153.81 g/mol

pg 336 37. The United States chemical industry produces more sulfuric acid (H2SO4), in terms of mass, than any other chemical. What is the mass of 3.25 mol of H2SO4 2 𝑚𝑜𝑙 𝐻 𝑥 1.008 𝑔 𝐻 1 𝑚𝑜𝑙 𝐻 1 𝑚𝑜𝑙 𝑆 𝑥 32.07 𝑔 𝑆 1 𝑚𝑜𝑙 𝑆 4 𝑚𝑜𝑙 𝑂 𝑥 16.00 𝑔 𝑂 1 𝑚𝑜𝑙 𝑂 =2.016 𝑔 𝐻 =32.07 𝑔 𝑆 =64.00 𝑔 𝑂 𝑚𝑜𝑙𝑎𝑟 𝑚𝑎𝑠𝑠 𝐻 2 𝑆 𝑂 4 =98.09 𝑔/𝑚𝑜𝑙 3.25 𝑚𝑜𝑙 𝐻 2 𝑆 𝑂 4 𝑥 98.09 𝑔 𝐻 2 𝑆 𝑂 4 1 𝑚𝑜𝑙 𝐻 2 𝑆 𝑂 4 =𝟑𝟏𝟗 𝒈 𝐻 2 𝑆 𝑂 4

pg 336 38. What is the mass of 4.35*10^-2 mol of zinc chloride (ZnCl2). 1 𝑚𝑜𝑙 𝑍𝑛 𝑥 65.38 𝑔 𝑍𝑛 1 𝑚𝑜𝑙 𝑍𝑛 2 𝑚𝑜𝑙 𝐶𝑙 𝑥 35.45 𝑔 𝐶𝑙 1 𝑚𝑜𝑙 𝐶𝑙 =65.38 𝑔 𝑍𝑛 =70.90 𝑔 𝐶𝑙 𝑚𝑜𝑙𝑎𝑟 𝑚𝑎𝑠𝑠 𝑍𝑛𝐶 𝑙 2 =136.28 𝑔/𝑚𝑜𝑙 4.35 𝑥 10 −2 𝑚𝑜𝑙 𝑍𝑛𝐶 𝑙 2 𝑥 136.28 𝑔 1 𝑚𝑜𝑙 𝑍𝑛𝐶 𝑙 2 = 5.93 g 𝑍𝑛𝐶 𝑙 2

pg 337 40. Determine the number of moles present in each compound. 22.6 g AgNO3 1 mole 169.9 g AgNO3 6.50 g ZnSO4 1 mole 161.5 g ZnSO4 35.0 g HCl 1 mole 36.5 g HCl = 0.133 mol = 0.0403 mol = 0.960 mol

pg 339 42. Ethanol (C2H5OH), a domestically produced fuel source, is often blended with gasoline. A sample of ethanol has a mass of 45.6g. How many carbon atoms does the sample contain? How many hydrogen atoms are present? How many oxygen atoms are present 45.6 g 1 mol 46.07 g = .990 mol 6.02*10^23 1 mol x 2 atoms C = 1.19*1024 C atoms 1 molecule C2H5OH x 6 atoms C = 3.59*1024 H atoms c) x 1 atom O = 5.96*1023 O atoms

pg 339 2.25 g Na2SO3 x 1 mol = 0.0178 mol 126.1 g 2.15*1022 Na+ ions 43. A sample of sodium sulfite (Na2SO3) has a mass of 2.25g. How many Na+ ions are present? How many SO3(2-) ions are present? What is the mass in grams of one formula unit of Na2So3 2.25 g Na2SO3 x 1 mol = 0.0178 mol 126.1 g 2.15*1022 Na+ ions 1.07*1022 So3 (2-) ions 2.09 * 10-22 g Na2So3/ formula unit

pg 339 52.0 g CO2 x 1 mol = 1.18 mol 44.0 g x NA = 7.11*1023 C atoms 44. A sample of carbon dioxide (CO2) has a mas of 52.0g. How many carbon atoms are present? How many oxygen atoms are present? What is the mass in grams of one molecule of CO2? 52.0 g CO2 x 1 mol = 1.18 mol 44.0 g x NA = 7.11*1023 C atoms x NA x 2 = 1.42*1024 O atoms 44.0 / NA = 7.31*10-23 g CO2/ molecule