VOGRO XM 2014 - nswers 1 What is the SI unit for amount of substance? 5 Which of the following has the largest covalent radius? gram carbon, kilogram fluorine, F * mole * silicon, Si millilitre sulfur, S litre chlorine, l 2 Mercury has a density of 13.6 g ml 1 at 0 o and 101 kpa. For this condition of temperature and pressure, what is the volume of 50.0 grams of mercury? * 3.68 ml 6 Which of the following statements concerning Hl is not correct? It is a strong acid in water. The oxidation state of chlorine is 1. 6.80 10 2 ml It is a stronger acid than HF. 0.272 ml 63.6 ml 36.4 ml * The bond between hydrogen and chlorine is primarily ionic. It is a gas at 25 o and 101 kpa. 3 How many protons, neutrons and electrons are there in a single 3 H ion? 7 Treatment of 12 H 22 O 11 (table sugar) with excess concentrated H 2 SO 4 yields a black residue (pure carbon) and water vapour. What is the maximum mass of carbon that can be obtained from exactly one gram of 12 H 22 O 11? one neutron, one proton, one electron 0.035 g * two neutrons, one proton, two electrons 0.083 g one neutron, three protons, two electrons three neutrons, one proton, one electron three neutrons, one proton, two electrons 0.12 g 0.27 g * 0.42 g 4 Which of the following exists as an atomic gas at 25 o and 101 kpa? hydrogen chlorine bromine sulfur * krypton 8 There are only two naturally-occurring isotopes of gallium. gallium-69: 68.925581 u gallium-71 70.924705 u If the weighted atomic mass of gallium is 69.723 u, then what is the percent abundance of gallium-71? 33.8% * 39.9% 50.7% 60.1% 2 / VOGRO XM 2014 UNIVRSITY OF WTRLOO 66.2%
9 Which pair of compounds is most similar in their physical and chemical properties? * Hl and Hr H 2 O and H 2 S 13 oth HlO 4 and Hl are strong acids. Which of the following provides evidence that HlO 4 is a stronger acid than Hl? When dissolved in water, both HlO 4 and Hl ionize completely. O 2 and SiO 2 H 3 OH and (OH) 3 Hl and NaOH The boiling point of HlO 4 is higher than that of Hl. ommercial preparations of concentrated HlO 4 are typically 70% HlO 4 by mass whereas commercial preparations of Hl are about 38% Hl by mass. 10 When the Kelvin temperature of a fixed amount of an ideal gas is doubled and the pressure is doubled, what is the combined effect on the volume of the gas? * The volume remains constant. * When dissolved in acetic acid (H 3 OOH), HlO 4 ionizes to a greater extent than does Hl. opper metal dissolves readily in a concentrated solution of HlO 4 but not in concentrated Hl solution. The volume increases by a factor of two. The volume increases by a factor of four. 14 What is the general formula of the hydrides formed by the elements () of group 15? The volume decreases by a factor of two. H The volume decreases by a factor of four. H 2 11 What is the correct electron arrangement for a nickel (Ni) atom? (The first number in each list refers to the number of electrons in the first shell; the second number refers to the number of electrons in the second shell; and so on.) 2, 6, 10, 10 10, 10, 8 2, 8, 2, 8, 2, 6 * 2, 8, 16, 2 2, 8, 8, 8, 2 12 Which set of coefficients properly balances the equation below? Zn(s) + g + (aq) Zn 2+ (aq) + g(s) 1, 1, 1, 1 2, 1, 2, 1 * 1, 2, 1, 2 2 H * H 3 H 4 15 Which second-period atom has the greatest number of unpaired electrons in its lowest energy state? * nitrogen, N oxygen, O fluorine, F carbon, boron, 16 Which of the following equations is not correct? r 2 + energy 2 r IF + energy l + + F F + e F + energy all of the above none of the above O 2 (g) O 2 (s) + energy * O 2 + energy O + O 2014 UNIVRSITY OF WTRLOO VOGRO XM / 3
17 Which combination of elements will most likely form an ionic compound? hydrogen and fluorine sodium and magnesium * magnesium and oxygen oxygen and chlorine silicon and oxygen 21 What volume does 11.0 kg of carbon dioxide occupy at 0 o and 101.3 kpa? 2.47 10 3 L * 5.60 10 3 L 11.0 L 577 L 247 L 18 solid sample of impure carbon is 84% by mass. How many carbon atoms are there in a 71.0 g sample? 2.5 10 24 2.1 10 24 * 3.0 10 24 3.0 10 25 2.5 10 25 19 What gas is produced when ammonium nitrate, NH 4 NO 3, is added to NaOH(aq) and the solution gently heated? hydrogen peroxide, H 2 O 2 oxygen, O 2 dinitrogen tetroxide, N 2 O 4 * ammonia, NH 3 nitric oxide, NO 20 What is the maximum amount of HNO 3 that can be obtained from 4.50 moles of NO 2 and 3.00 moles of H 2 O according to the following equation? 3 NO 2 + H 2 O 2 HNO 3 + NO * 3.00 moles 6.00 moles 7.50 moles 6.75 moles 22 In the reaction below, which element is reduced? 8 KI + 9 H 2 SO 4 4 I 2 + 8 KHSO 4 + H 2 S + 4 H 2 O potassium (K) iodine (I) hydrogen (H) * sulfur (S) oxygen (O) 23 When 25 ml of 0.10 mol L 1 Hr(aq) is mixed with 25 ml of 0.20 mol L 1 KOH(aq), what is the ph of the final solution at 25 o? 1.00 1.30 7.00 * 12.70 13.00 24 What is the formula of copper(ii) nitride? * u 3 N 2 u 2 N u(no 3 ) 2 u 2 NO 3 u 2 N 3 5.00 moles 4 / VOGRO XM 2014 UNIVRSITY OF WTRLOO
25 What is the pressure of the gas in the apparatus below if the atmospheric pressure is 764 mmhg? 28 In an experiment, a 1.52 gram sample of solid KlO 3 is decomposed by heating to produce Kl and 310 ml of O 2 gas at 25.0 o and 103 kpa. What is the percent yield for this experiment? Gas 48 mm 59% * 69% 78% 87% mercury (Hg) 22 mm 96% 26 mmhg 70 mmhg 738 mmhg * 790 mmhg 834 mmhg 29 nalysis of a solution of o 2 (SO 4 ) 3 establishes that the concentration of SO 4 2 is 0.060 mol L 1. What is the concentration of o 3+ in this solution? 0.010 mol L 1 0.030 mol L 1 * 0.040 mol L 1 26 Suppose the atomic mass scale had been set up with calcium (a) assigned a mass of 10 u. What would be the approximate atomic mass of oxygen? 0.060 mol L 1 0.090 mol L 1 1.6 u * 4.0 u 8.0 u 64 u 160 u 27 n unidentified metal X forms a compound with chlorine in which 1.036 g of X are present for every 0.3545 g of chlorine. The empirical formula of the compound is Xl 2. What is the atomic symbol for X? Hg Mg a Rh * Pb 30 Which of the following is an isomer of diethyl ether, H 3 H 2 OH 2 H 3? butanal, H 3 H 2 H 2 HO dimethyl ether, H 3 OH 3 * t-butyl alcohol, (H 3 ) 3 OH butanoic acid, H 3 H 2 H 2 OOH butan-2-one, H 3 H 2 OH 3 31 Which compound contains oxygen in the highest (most positive) oxidation state? KO 3 K 2 O 2 * F 2 O K 2 O NO 2 2014 UNIVRSITY OF WTRLOO VOGRO XM / 5
32 Which of the following statements is not correct? eviations from ideal gas behaviour are more significant at high pressures. ttractive intermolecular forces cause a decrease in the observed pressure of a gas compared to what is predicted for an ideal gas. 35 Which of the following is the Lewis structure (i.e., the best electron dot structure) for the N 3 ion? * eviations from ideal gas behaviour are more significant at very low temperatures. * t very high pressures, the observed molar volume of a gas is smaller than what is predicted for an ideal gas. For low to moderate pressures, attractive intermolecular forces are the primary cause of deviations from ideal gas behaviour. N N N 33 solution has [H + ] = 3.7 10 3 mol L 1. What is the ph of this solution? * 2.43 3.57 3.70 4.04 5.60 36 gaseous compound contains hydrogen, carbon and nitrogen. If combustion of 1.0 L of the compound in oxygen yields 2.0 L O 2, 3.5 L of H 2 O and 0.50 L of N 2, all measured at the same temperature and pressure, what is the empirical formula of the compound? HN H 2 N 2 4 H 7 N H 4 N 7 * 2 H 7 N 34 container of helium gas, initially at 217 kpa and 5.00 o, is heated to 80.0 o. The container is opened briefly to allow some gas to escape and then it is closed. If the final pressure is 93.0 kpa, what fraction of the helium gas remains in the container? 0.15 * 0.34 0.42 0.58 0.79 37 In a well-insulated container, an endothermic reaction takes place. When the reaction is done, the temperature of the contents will be higher than before the reaction began higher or lower than at the start of the reaction depending on the masses of reactants used independent of the heat capacities of the substances involved the same as before the reaction began * be lower than before the reaction began 6 / VOGRO XM 2014 UNIVRSITY OF WTRLOO
38 Which of the following is less soluble in hot water than in cold water? glucose, 6 H 12 O 6 * methane, H 4 silver chloride, gl silver nitrate, gno 3 sodium hydroxide, NaOH 39 t high temperatures, hydrogen iodide (HI) reacts reversibly according to the following equation. 2 HI(g) H 2 (g) + I 2 (g) In an experiment, an initial reaction mixture containing 0.100 mol each of HI, H 2 and I 2 at room temperature is prepared and then heated to a high temperature. fter some time has passed, the amount of HI in the system is found to be.0.120 moles. What is the amount of H 2 in the system at that time? 0.120 moles 0.110 moles * 0.090 moles 0.080 moles 0.060 moles 40 6.00 mol L 1 aqueous solution of sl is 58.0% sl by mass. What is the density of this solution? Molar masses 0.586 g/ml (in g/mol) H 2 O, 18.02 0.842 g/ml sl, 168.35 1.01 g/ml * 1.74 g/ml 16.3 g/ml 2014 UNIVRSITY OF WTRLOO VOGRO XM / 7