The majority of the mass of the atom is located in the___

Achemist has dissolved a certain substance in water. the chemist knows that more of the substance could be dissolved into the water before it stops dissolving. therefore

The equation below shows the reaction of zinc with hydrochloric acid (hcl). zn (s) + 2 hcl (aq) —> zncl2 (aq) + h2 (g) what will happen if the concentration of hcl is decreased? a. more zncl2 will be produced. b. the reaction rate will slow down. c. the hydrochloric acid will become more acidic. d. the reaction will produce water instead of hydrogen gas.

Stoichiometry- i need with 14 and 15! an explanation would be appreciated!