Preparation of 2% and 4 % HNO3 from 35% HNO3

35%nitric acid means 35g of nitric acid in 100ml water.

So, considering it a homogenous solution, now calculate in how much solution there is 2g. Then separate that volume and make up to 100ml. Its easy method to calculate.

2g of nitric acid = (2 * 100 ) / 35 = 5.71ml of water.

Now, that implies 5.71ml of 35% nitric acid has 2g of nitric acid.

Therefore, for 100 ml preparation take 5.71ml of 35% nitric acid and add 94.29ml of water. It becomes 2% nitric acid

For 1000 ml 2% HNO3 preparation take 57.1 ml 35% HNO3 and add 942.9 ml MQ water

For 1000 ml 4% HNO3 preparation take 114.29 ml 35% HNO3 and add 885.7 ml MQ water