can you show me the formula for this problem.

Question

calculate the grams of NaOH present in 9.0 ml of a 8.0 (m/v) NaOH solution.

thank you

Answer 1

8.0 what? 8.0 % w/v?
8.0 % w/v means 8 g NaOH/100 mL solution or 80g/1000mL = 80g/L. mols NaOH in 80g is 80/40 = about 2 so this is 2M.
Then mols = M x L = 2M x 0.009L = ? mols NaOH

Answer 2

9.0 mL solution= ? g NaOH

8g NaOH
9.0 mL solution ------------
100 mL soln

= 0.72g NaOH

Answer 3

Edited*
9.0 mL solution= ? g NaOH


(9.0 mL solution x (8g NaOH)
=72
Divide answer to 100 mL solution
*cross out mL solution

= 0.72g NaOH