Give the answer with the appropriate number of significant figure. a. 0.011 + 0.09 = b. 0.31 times 1.2 = (2) Calcium is an example of: a. a halogen. b. an alkali metal. c. a noble gas. d. an alkaline earth metal. (2) Chlorine is: a. a halogen. b. an alkali metal. c. a noble gas. d. a substance brought to earth by aliens. (2) When you chemically react 2.0 grams of reactants you will make 2.0 grams of This is an example of the law of conservation of mass, proposed by: a. Ernest Rutherford. b. Joseph Proust. c. Antoine Lavoisier. d. John Dalton. (2) The properties of a pure substance are determined by: a. temperature and volume. b. mass and volume. c. time and place. d. structure and composition.