Question

3l of water are added to 2l of 5molar hcl solution .what is the molarity of resulting solution

Answer 1

3 answers · Chemistry 

 Best Answer

If you use the formula directly, you will get the molarity=2 mol/L 
which is correct. 

Alternative Method: 

1 litre of original solution contains = 5 moles of HCl ('coz Molarity=5M) 
2 litres of original solution contains= 10 moles of HCl 

Now, since the tot. volume is 2+3=5 litres and the no. of moles of HCl are the same, we get: 

5 litres of soln. contains = 10 moles of HCl 
1 litre of soln. ontains = 2 moles of HCl 

Thus, Molarity of resulting soln. = 2M 

Yes, this is a question of dilution only.