Chemistry General Midterm Questions & Answers

Chemistry General Midterm Questions & Answers A cube of iron at 20 C is placed in contact with a cube of copper at 60. Which statement describes the initial flow of heat between the cubes? - CORRECT ANSWER - Heat flows from the copper cube to the iron cube. A mixture of crystals of salt and sugar is added to water and stirred until all solids have dissolved. Which statement best describes the resulting mixture? - CORRECT ANSWER - The mixture is homogeneous and cannot be separated by filtration A student determined the heat of fusion of water to be 88 calories per gram. If the accepted value is 80. calories per gram, what is the student's percent error? - CORRECT ANSWER - 10% An ion that consists of 7 protons, 9 neutrons, and 10 electrons has a net charge of - CORRECT ANSWER - 3- At 1 atmosphere of pressure, 25 grams of a compound at its normal boiling point is converted to a gas by the addition of 34,400 Joules. What is the heat of vaporization for this compound, in Joules per gram? - CORRECT ANSWER - 1376 At STP, which gas will diffuse more rapidly than Ne? - CORRECT ANSWER - He At the same temperature and pressure, 1.0 liter of CO(g) and 1.0 liter of CO2(g) have - CORRECT ANSWER - equal volumes and the same number of molecules Compared to an atom of phosphorus-31, an atom of sulfur-32 contains - CORRECT ANSWER - one more proton Given the balanced equation 2KI+F2---2KF + I2 Which type of chemical reaction does this equation represent? - CORRECT ANSWER - single replacement Given the unbalanced equation __Al + __CuSO4--___Al2(SO4)3 + ____Cu When the equation is balanced using the smallest whole-number coefficients, what is the coefficient of Al? - CORRECT ANSWER - 2 How do the energy and the most probable location of an electron in the third shell of an atom compare to the energy and the most probable location of an electron in the first shell of the same atom? - CORRECT ANSWER - In the third shell, an electron has more energy and is farther from the nucleus In an experiment using a calorimeter, the following data were obtained: