Question

what will be the concentration in gram per litre of 5 gram of naoh in 200 ml solution​

Answer 1

The solution is 2.50% NaOH (5/(200*0.9982)*100%)=2.5047%~2.50%

The density of a 2.5% solution of NaOH is 1.0263 g/mL

The total mass of the solution is 204.6 g (5 g NaOH+ 200mL*0.9982 g/mL) so the total volume is 204.6 g/( 1.0263g/mL)=199.36mL=0.19936L

Now the Molarity can be calculated.

5 g/(39.997 g/mol)/0.19936L=0.62705M~0.627M