Kindly tell me the correct answer with some explanation (10 pts +thanks for the best answer)?

Question

In most chemical reactons, reaction rate may be calculated. Which term must always be written in the denominator of the reaction rate?

a)mass e.g. in grams

b)Volume e.g.in mL

c)Molarity e.g. in moles/litre

d)time e.g. in seconds

Answer 1

second

The correct expressions to indicate rate of a reaction are:

moles / sec.

grams /sec

Answer 2

d) time in seconds

Answer 3

The denominator of any rate value is ALWAYS time, as in miles per hour or flagons per fortnight or grams per second.

Answer 4

mass in gram