Chem 103 Module 1 Exam

CHEM 103 MODULE 1 EXAM 2022 Question 1 Click this link to access the Periodic Table. This may be helpful throughout the exam. 1. Convert 845.3 to exponential form and explain your answer. 2. Convert 3.21 x 10 -5 to ordinary form and explain your answer. 1. Convert 845.3 = larger than 1 = positive exponent, move decimal 2 places = 8.453 x 10 2 2. Convert 3.21 x 10 -5 = negative exponent = smaller than 1, move decimal 5 places = 0. Question 2 Click this link to access the Periodic Table. This may be helpful throughout the exam. Using the following information, do the conversions shown below, showing all work: 1 ft = 12 inches 1 pound = 16 oz 1 gallon = 4 quarts 1 mile = 5280 feet 1 ton = 2000 pounds 1 quart = 2 pints kilo (= 1000) 1/100) milli (= 1/1000) deci (= 1/10) centi (= 1. 24.6 grams = ? kg 2. 6.3 ft = ? inches 1. 24.6 grams x 1 kg / 1000 g = 0.0246 kg 2. 6.3 ft x 12 in / 1 ft = 75.6 inches please always use the correct units in your final answer Question 3 Click this link to access the Periodic Table. This may be helpful throughout the exam. Do the conversions shown below, showing all work: 1. 28 oC = ? oK 2. 158 oF = ? oC 3. 343 oK = ? oF 1. 28 oC + 273 = 301 oK oC → oK (make larger) +273 2. 158 oF - 32 ÷ 1.8 = 70 oC oF → oC (make smaller) -32 ÷1.8 3. 343 oK - 273 = 70 oC x 1.8 + 32 = 158 oF oK → oC → oF Question 4 Click this link to access the Periodic Table. This may be helpful throughout the exam. Be sure to show the correct number of significant figures in each calculation. 1. Show the calculation of the mass of a 18.6 ml sample of freon with density of 1.49 g/ml 2. Show the calculation of the density of crude oil if 26.3 g occupies 30.5 ml. 1. M = D x V = 1.49 x 18.6 = 27.7 g 2. D = M / V = 26.3 / 30.5 = 0.862 g/ml Question 5 Click this link to access the Periodic Table. This may be helpful throughout the exam. 1. 3.0600 contains ? significant figures. 2. 0.0151 contains ? significant figures. 3. 3.0600 ÷ 0.0151 = ? (give answer to correct number of significant figures) 1. 3.0600 contains 5 significant figures. 2. 0.0151 contains 3 significant figures. 3. 3.0600 ÷ 0.0151 = 202.649 = 203 (to 3 significant figures for 0.0151) Question 6 Click this link to access the Periodic Table. This may be helpful throughout the exam. Classify each of the following as an element, compound, solution or heterogeneous mixture and explain your answer. 1. Coca cola 2. Calcium 3. Chili 1. Coca cola - is not on periodic table (not element) - no element names (not compound) appears to be one substance = Solution 2. Calcium - is on periodic table = Element 3. Chili - is not on periodic table (not element) - no element names (not compound) appears as more than one substance (meat, beans, sauce) = Hetero Mix Question 7 Click this link to access the Periodic Table. This may be helpful throughout the exam. Classify each of the following as a chemical change or a physical change 1. Charcoal burns 2. Mixing cake batter with water 31 3. Baking the batter to a cake 1. Charcoal burns - burning always = chemical change 2. Mixing cake batter with water - mixing = physical change 3. Baking the batter to a cake - baking converts batter to new material = chemical change Click this link to access the Periodic Table. This may be helpful throughout the exam. Show the full Nuclear symbol including any + or - charge (n), the atomic number (y), the mass number (x) and the correct element symbol (Z) for each element for which the protons, neutrons and electrons are shown - symbol should appear as follows: xZy +/- n 31 protons, 39 neutrons, 28 electrons 31 protons = Ga31, 39 neutrons = 70Ga31, 28 electrons = (+31 - 28 = +3) = 70Ga +3 Question 9 Click this link to access the Periodic Table. This may be helpful throughout the exam. Name each of the following chemical compounds. Be sure to name all acids as acids (NOT for instance as binary compounds) 1. PF5 2. Al2(CO3)3 3. H2CrO4 1. PF5 - binary molecular = phosphorus pentafluoride 2. Al2(CO3)3 - nonbinary ionic = aluminum carbonate Question 8 2 3 3 3 3. H2CrO4 - nonbinary acid = chromic acid incorrect fluoride prefix Question 10 Click this link to access the Periodic Table. This may be helpful throughout the exam. Write the formula for each of the following chemical compounds explaining the answer with appropriate charges and/or prefixes and/or suffixes. 1. Carbon monoxide 2. Manganese (IV) acetate 3. Phosphorous acid 1. Carbon monoxide - ide = binary, mono = 1 O = CO 2. Manganese (IV) acetate - Mn +4 , C2H3O -1 = Mn(C2H3O2)4 3. Phosphorous acid - nonbinary acid of H + phosphite (PO -3 ) = H PO