The mole ratio of hydrogen molecules to sulfur atoms in the equation H2 + S = H2S is equal to: A) 2 to 1
B) 16 to 1
C) 1 to 32
D) 4 to 2
E) 1 to 1

The answer for #3 is c but i don't know why

Consider the following reaction at equilibrium. 2co2 (g) 2co (g) + o2 (g) h° = -514 kj le châtelier's principle predicts that the equilibrium partial pressure of co (g) can be maximized by carrying out the reaction a. at high temperature and high pressure b. at high temperature and low pressure c. at low temperature and low pressure d. at low temperature and high pressure e. in the presence of solid carbon

How many protons, electrons, and neutrons are in each of the following isotopes? a. zirconium-90 b. palladium-108 c. bromine-81 d. antimony-123