What is the approximate mass of the most abundant naturally occurring cl2 molecule?

The approximate mass of the most abundant naturally occurring cl2 molecule is 70, there are two isotopes of chlorine and which occurs most abundantly is chlorine 35. 35 is an approximate mass of chlorine atom and when it makes a molecule it becomes cl2  it means mass will be doubled so 70 is the approximate mass of cl2 molecule which is most abundant naturally occurring.

D-no effect on the rate

Ithink this is what you meant. the temperature at which a liquid begins to boil is called the boiling point. the boiling point of water is 212°f or 100°c.  and at that point will start to turn into steam (gas)