Chem 16 Reviewer

CHEM 16 FIRST LONG EXAM REVIEW I. MULTIPLE CHOICE. Answer the following by writing the best answer from the choices. 1. Which of the following is a physical change?  the growing seedling forms new leaves  the golden bridge becomes brownish with age  the inability of gold to react with water  the melting of chocolate  Melting is a phase change, which is an example of physical change. 2. Which of the following is an extensive property?  the density of ethanol is 0.789 g/mL  the molecular weight of hemoglobin is 65,000 g/mol  the melting point of tungsten is 3370 °C  the heat content of a solution is 3.5 kcal  Density, melting point, and molecular weight do not depend on the amount of substance. 3. The hydrocarbons octane (C8H18), hexane (C6H14), and butane (C4H10) illustrate the:  Law of Conservation of Matter  Law of Multiple Proportions  Law of Definite Proportion  Law of Constant Composition  LOMP is illustrated here since C and H are found in different mole ratios in the given compounds. 80 81 82 4. The three species Se, Br and Kr have the same  atomic mass.  number of protons.  number of neutrons.  number of electrons.  The three species have 34, 35 and 36 protons, respectively. They all have 46 neutrons. Their number of electrons are equal to their respective number of protons. 5. Which of the following best represents a substance?  ice cream  bread  snow  ink  Snow is mostly pure water (as ice), while the others are mixtures. 6. Antoine Lavoisier, the “father of chemistry”, listed lime as a chemical element in his table of 33 known elements. Which of the following observations shows that lime CANNOT be an element?  Lime and carbon dioxide are produced when limestone is roasted.  Lime melts at a temperature of 2572 °C.  Lime is solely produced when a certain soft metal is heated in air.  Lime reacts with water, generating a large amount of heat.  The highlighted choice shows that lime is composed of at least two different elements,...