ap classroom questions - only for use by fellow teachers with accredited access to ap classroom. please respect. 4.4 mc questions 1. a student places a sample of a pure metal in a crucible and heats it strongly in air. data from the experiment are given in the table above. the final mass was determined after the sample was cooled to room temperature. which of the following statements related to the experiment is correct? a the mass of the sample decreased, so physical changes occurred as the metal first melted and then boiled out of the crucible. b the mass of the sample increased, so a chemical change occurred when bonds formed between the metal and another substance. c there was nothing for the metal to react with, so only a physical change could have occurred. d the sample was only heated, so neither a physical nor a chemical change occurred. 2. a student mixes 20.0g of white kcl crystals with distilled water in a beaker. after the mixture was stirred, no crystals are visible and the solution is clear. after several days, all of the water evaporates and white crystals are found in the beaker. which of following pieces of experimental evidence would best help the student to conf