Hi everyone, I'm having trouble with this question:

"Calculate the number of moles required to make 250ml of 100mM KMnO

_{4}Give your answer in moles to two significant figures omitting the units"

I didn't do A-Level chemistry only Biology, and I've watched a few videos and read a few articles on how to get the atomic mass etc and it's embarrassing as to why I don't quiet know what this question is asking of me. I know the molecular mass is 158.

I'm sorry to ask such a basic question. one part that i'm confused upon is the 100mM is that 0.1?

Any help would be very much appreciated as I also need to answer the sister question which is

"Now that you know how many moles of KMnO

_{4} are required and you know the molecular mass, you should your previous answers to calculate what mass of KMnO

_{4} you require to make 250ml of 100 mM"

thank you for your time and again, any help would be so very much appreciated

Kindest regards

Ade