How much pure alcohol be added to 400 ml of a `15 %` solution to make its strength `32 %` ?

How much pure alcohol be added to 400mlofa15% solution to make its strength 32%?

20 mL of a solution of sulphuric acid neutrlise 21.2 mL of 30 % solution of sodium carbonate. How much water should be added to 100 mL of this solution to bring down its strength to decinormal ?

20 mL of a solution of H_2SO_4 neutralises 21.2 mL of 30% solution (w/v) of Na_2CO_3 . How much water should be added to each 100 mL of the solution to bring down its strength to decinormal ?

How much pure alcohol has to be added to 400 mL of a solution containing 15% of alcohol to change the concentration of alcohol in the mixture to 32%?

20 mL of a solution os sulphuric acid neuitralise 21.2 mL of 30% soution of sodium carbonete. How much water should be added to 100 mL of this solutio to bring down its down its strength to decinoral?

A 15% alcohol solution means