Question

How can I make 100ml 0f 2N of HCl? purity is 35% and density is given as 1.18 g/mL

Answer 1

What the concn of the HCl you have? that's
1000 mL x 1.18 g/mL x 0.35 x (1/36.5) = approx 11 N.
Then mL1 x N1 = mL2 x N2
100 mL x 2N = mL2 x 11N
Calculate mL2. That is approx 18 mL.
So take 18 mL of the good stuff, add to a 100 mL volumetric flask, add distilled water to the mark on the flask, mix thoroughly, stopper. I've estimated these numbers; you MUST go through and do them more accurately.

Answer 2

SAFETY NOTE WHEN USING/MIXING STRONG ACID SOLUTION IN WATER: Add X-ml of HCl needed into a small quantity of water ~ 40-ml or so, then dilute to needed volume. Adding water directly into 18 ml of Concentrated HCl will generate so much heat that splash-back is possible and very dangerous. Serious injury can occur. By adding concentrate into a small quantity of water (less that total soln vol) 1st, the chance of acid flash-back is eliminated as the acid is ionized much more slowly and over-heating is not a problem. Always wear safety glasses, rubber gloves and clothing protection when mixing any solutions. Good Luck.