Question

3. A solution is prepared by dissolving 3.65g of HCl in 500ml of the solution .Calculate the molarity of the solution. Determine the volume of this solution required to prepare250ml of 0.001M solution.

Answer 1

Answer:1)molarity=0.2M

2)volume=1.25ml

Explanation:1)Given,

Volume V=500ml

Weight W=3.65g

Molecular Mass M=1+35.5=36.5gm/mol

Molarity S=?

Then,

W=(SVM)/1000

Or,S=W×1000/V×M

Or,S=3.65×1000/500×36.5

Therefore,Molarity S=0.2M

2)Let,

S1=0.2M V2=250ml S2=0.001M

V1=?

Now,V1S1=V2S2

or,V1=250×0.001/0.2

Therefore,V1=1.25ml.