How to prepare a percent solution from molar ,normal and another percent solution?

Percent solution:

The percentage is very common to express the concentration of a solution. Percent means per 100 parts where parts refer to a measure of mass (μg, mg, g, kg etc.) or volume (μL, mL, L etc.). In percent solutions, the amount (weight or volume) of a solute is expressed as a percentage of the total solution weight or volume. Percent solutions can take the form of weight/volume % (w/v %), weight/weight % (w/w %), or volume/volume % (v/v %). 

Percent solution preparation:

Preparation of 10%w/v NaCl solution-

It is very easy to prepare a percent solution. At first we take 10g of NaCl in a volumetric flask and add distilled water to it up to 100 ml, mixing them well. Our 10%w/v NaCl solution is prepared.

Preparation of 80%, 250ml Ethanol solution:

Here, I give you a shortcut idea to solve this problem.

Suppose, x=amount of %

                  Y=desire volume

So the formula is =x*y/100

                               = (80*250/100) ml

                              =200ml

Then we take 200ml ethanol solution in a volumetric flask and add distilled water up to 250 ml.

Preparation of 5%HCl from 10%HCl solution:

To make a percent solution from another percent solution is easier. Here, we apply a formula and that is    C₁ V₁=C₂ V₂

                                                                      10* V₁ =5*100

                                                                      V₁=5*100/10

                                                                           =50ml

So we take 50ml HCl solution and add distilled water up to 100 ml of the volumetric flask.

Preparation of 50%H₂SO₄ from 2M H₂SO₄ solution:

To prepare a percent solution from a molar solution first, we have to calculate the percent solution into 1ml.

50% H₂SO₄  means …

100ml have 50g H₂SO₄

1 ml have=50/100 ml

                =0.5ml

Again,1000 ml 1M H₂SO₄  =98g

         1000 ml 2M H₂SO₄ =2*98

                                           =196g

So 196g is in 1000ml

    0.5g is in =1000*0.5/196 ml

                      =2.55 ml

So we have to take 2.55ml from 2M H₂SO₄  solution into a volumetric flask and add distilled water up to 100 ml.

Preparation of 2%H₂SO₄ from 2N H₂SO₄ solution:

To prepare a percent solution from a normal solution at first, we have to calculate the percent solution into 1ml.

2% H₂SO₄  means …

100ml have 2g H₂SO₄

1 ml have=2/100 ml

                =0.02ml

Again,1000 ml 1N H₂SO₄  =49g

         1000 ml 2N H₂SO₄ =2*49

                                           =98g

So 98g is in 1000ml

0.02 g is in =1000*0.02/98 ml

                      =0.2 ml

So we have to take 0.2ml from 2N H₂SO₄  solution into a volumetric flask and add distilled water up to 100 ml.