Chemistry 121 Worksheet 7 Notes 1 Oregon State University Dr Richard L Nafshun Sketch a cartoon of the PTE Periodic Table of the Elements Identify the metal and non metal regions with labels and a staircase What charges do the metals obtain Do metals lose or gain electrons How many What charges do the nonmetals obtain Do non metals lose or gain electrons How many What are molecules composed of Give three examples What are ionic compounds composed of Give three examples In forming ionic compounds Metals lose electrons Group 1 lose 1 Group 2 lose 2 Al loses 3 Non metals gain electrons Group 18 gain 0 Group 17 gain 1 Group 16 gain 2 Group 15 gain 3 Group 14 gain 4 In forming molecules non metals form bonds in which Group 17 form 1 bond Group 16 form 2 bonds Group 15 form 3 bonds Group 14 form 4 bonds Samples of molecules include H2O CH4 CO2 C8H18 2 The chemical formula of lithium phosphate is Li3PO4 The chemical formula of copper I phosphate is Cu3PO4 The chemical formula of iron II phosphate is Fe3 PO4 2 The chemical formula of ammonium carbonate is NH4 2CO3 The chemical formula of ammonium sulfide is NH4 2S 3 The chemical formula of phosphorous pentachloride is PCl5 The chemical formula of carbon dioxide is CO2 4 Identify two elements He Ar Identify two compounds CaS NO Identify two homogeneous mixtures Same throughout NaCl milk Identify two heterogeneous mixtures Explain Different throughout orange juice pizza granite 5 A student measures the length of a crystal to be 0 04678 cm A Express this length in meters B Express this length in km C Express this length in inches Given 1 inch 2 54 cm D Express this length in mm A 1m 0 04678 cm 100 cm 4 678 x 10 4 m B 1 km 4 678 x 10 4 m 1000 m 4 678 x 10 7 km C 1 inch 0 04678 cm 2 54 cm 0 01842 inch D 10 mm 0 04678 cm 1 cm 0 4678 mm 6 Determine the number of protons neutrons and electrons in each of the following 212 2 Pb C 12 4C 235 2 U 14 7 p 82 6 6 92 n 212 82 130 14 6 8 12 6 6 235 92 143 e82 2 80 6 6 4 10 92 2 90 What are isotopes Give an example Species with the same number of protons but different number of neutrons 14 C and 12C 8 Determine the molar masses AKA atomic masses of Ne Ca S and Na Ne 20 179 g mol Ca 40 08 g mol S 32 06 g mol Na 23 00 g mol 9 Determine the molar masses of calcium hydroxide ammonium carbonate and CuF2 Ca OH 2 74 10 g mol NH4 2CO3 96 07 g mol CuF2 101 55 g mol 10 A student obtains 5 550 x 1024 water molecules Calculate the mass of this sample 1 mol 6 022x10 water molecules 5 550 x 1024 water molecules 11 23 18 02 g 166 1 1 mol g water A student obtains 96 00 grams of oxygen gas O2 How many moles of O2 are present How many oxygen molecules are present 1 mol 96 00 g O2 32 00 g 3 000mol O2 6 022 x10 23 molecules 1 mol 1 807 x 1024 O2 molecules 3 000mol O2 12 Given the following reaction C3H8 5 O2 3 CO2 4 H2O Assume that 88 22 g of propane react with excess oxygen Calculate A the number of moles of propane that react 1mol 2 000 mol propane 44 11g 88 22 g C3H8 B the number of molecules of propane that react 6 022 x10 23 molecules 1 204 x 1024 propane molecules 1 mol 2 000 mol propane C the number of moles of carbon dioxide and water that are formed 3 mol CO 2 2 000 mol propane 1 mol C 3 H 8 6 000 mol CO2 D the number of grams of carbon dioxide and water that are formed 44 01g 1 mol CO 2 6 000 mol CO2 264 1 g CO2 4 mol H 2 O 8 000 mol H2O 2 000 mol propane 1 mol C 3 H 8 18 01 g 144 1 g H2O 1 mol H 2 O 8 000 mol H2O E the number of molecules of carbon dioxide and water that are formed 6 022 x10 23 molecules 3 613 x 1024 CO2 molecules 6 000 mol CO2 1 mol 6 022 x10 23 molecules 4 818 x 1024 H2O molecules 1mol 8 000 mol H2O F the number of moles grams and molecules of oxygen that are used up 5 mol O 2 2 000 mol propane 1 mol C 3 H 8 10 00 mol O2 6 022 x10 23 molecules 6 022 x 1024 O2 molecules 1mol 10 00 mol O2 32 00 g 1 mol O2 10 00 mol O2 320 0 g O2 G a student collects 23 50 grams of CO2 What is the percent yield 23 50 g actual mass Percent Yield theoretical mass 100 264 1 g 100 8 898 13a Balance C11H24 O2 CO2 H2O How many moles of water are produced if four moles of C11H24 are consumed C11H24 17 O2 11 CO2 12 H2O 12 moles H 2 O 48 moles H2O 4 moles of C11H24 1 mole C11 H 24 13b Balance Li O2 Li2O How many moles of Li2O are produced if eight moles of Li are consumed 2 Li 1 O2 Li2O 2 Or 4 Li O2 2 Li2O 2 moles Li 2 O 4 moles Li2O 4 mole Li 8 moles of Li 14 Write and solve two of your own sig fig questions here How many sig figs in 0 02230 4 12 300 12 33 151 7 15 A compound has a density of 0 933 g mL What is the volume of 34 8 g d 16 mass volume 0 933 g mL 34 8 g 37 3 mL volume Determine the mass percent composition of lithium sulfate Li2SO4 109 94 g mol 2 Li 2 6 941 g mol 13 88 g mol 1 S 32 06 g mol 4 O 64 00 g mol 13 88 g mol 100 12 63 109 94 g mol Li 32 06 g mol 100 29 16 109 94 g mol S O 17 A student measures the length of a crystal to be 0 0225 cm A Express this length in meters B Express this length in km C Express this length in inches Given 1 inch 2 54 cm D Express this length in mm 18 64 00 g mol 100 58 21 109 94 g mol A 1m 0 0225 cm 100 cm 2 250 x 10 4 m B 1 km 2 250 x 10 4 m 1000 m 2 250 x 10 7 km C 1 inch 0 0225 cm 2 54 cm 0 00886 inch D 10 mm 0 0225 cm 1 cm 0 …