We’re asked to determine which of the given reactions is most likely to proceed at the greatest rate.
Reaction rates are influenced by 4 factors:
1. Concentration: for a reaction to occur, molecules must collide.
Increasing the number of molecules in a container increases their collisions and thereby causes the rate to increase.
2. Surface area: the greater the surface area, the greater the chance for the reaction to occur and the faster the reaction can occur.
The surface area depends on the geometry, phase or structure of the compound.
Which of the following reactions is most likely to proceed at the greatest rate?
A. Zn(s) + S(s) → ZnS(s)
B. H2(g) + I2(s) → 2HI(g)
C. Cu(s) + Cl2(g) → CuCl2(s)
D. 2KOH(aq) + H2SO4(aq) → 2H2O(l) + K2SO4(aq)