Perform the following mathematical operation, and
report the answer to the
appropriate number of
significant figures.
140.3 - 120.124 = [?]

12. complete each of the following word equations for synthesis reactions. a. sodium + oxygen -> b. magnesium + fluorine -> 13. complete and balance the equations for the decomposition reactions. a. hgo -> [with the triangle heat symbol above the arrow] b. h2o(l) -> [with "electricity" written above the arrow]

The number of neutrons is equal to the atomic number minus the atomic mass. a. true b. false

Describe what happens to the molecules as water goes from ice to liquid to vapor. be sure to explain what happens to the temperature during the phase changes.