Start with 0.98g of NaOH how many moles of NaOH did we start with?

The answer is 0.0245 moles

(1) Find the molar mass of NaOH (it is the sum of atomic masses of its elements):

Mr (NaOH) = Ar (Na) + Ar (O) + Ar (H) = 23 + 16 + 1 = 40 g/mol

So 1 M of NaOH has 40g

(2) Find the number of moles of 0.98g:

1 M has 40g.

x M has 0.98 g.

1M : 40 g = x : 0.98 g

x = 1M * 0.98 g : 40 g = 0.0245M