Hich of the following statements is true about what happens during a chemical reaction?
a. bonds of the reactants are broken, and bonds of the products are formed.
b. bonds of the reactants are formed, and bonds of the products are broken.
c. the bonds of both the reactants and the products are broken.
d. the bonds of both the reactants and the products are formed.

Liquid ammonia is produced at high temperatures and under great pressure in a tank by passing a mixture of nitrogen gas and hydrogen gas over an iron catalyst. the reaction is represented by the following equation. n2(g) + 3h2(g) → 2nh3(g) changing all but one experimental condition will affect the amount of ammonia produced. that condition is a) increasing the concentration of both reactants b) changing the temperature within the tank c) decreasing the pressure within the tank. d) increasing only the amount of nitrogen present.

In order for a high temperature boiler or steam engine to produce superheated water, or steam: the heat source must be greater than 100°c the water must be permitted to evaporate quickly the system must be sealed and become pressurized above atmospheric pressure the vapor pressure must be kept below 760 mm(hg)

Which of the following are in a chemical family a. ca, sc, k b. cu, ag, au c. so, ge, sb