Here is the pretest for Chess.com University’s Chess 014 course:
2. The atomic number of calcium is 20 and its atomic mass is 40 amu. Which of the following does the given information imply?
a. Calcium tends to have more protons than neutrons.
b. Calcium forms anions in HCl.
c. Calcium has 20 protons.
d. Calcium cannot bond with any metals.
1. Which of the following is a difference between an endothermic and an exothermic chemical reaction?
a. Energy is only conserved in exothermic reactions.
b. The system absorbs heat during an endothermic reaction while the system releases heat during an exothermic reaction.
c. Endothermic reactions fuse nuclei whereas exothermic reactions cause nuclear fission.
d. Endothermic reactions are never spontaneous whereas exothermic reactions can be spontaneous.