Question

What mass of salt must be added to 250ml water to prepare 12.5% solution?

Answer 1

Answer:

224

Explanation:

this will be alright if u set an example of setting thoese things

Answer 2

The mass of salt must be added to 250ml water to prepare 12.5% solution is 35.71gm.

A 12.5% salt solution means that in a 100mL of solution, 12.5 gm of the salt (solute) is present.

A solution is a mixture of solute and solvent.

Solution = Solute + Solvent.

Here, solute is the salt and solvent is water.

Also, we know that 1 mL of water = 1gm of water.

Hence, weight of 250mL water = 250gm.

If we consider the weight of solute(salt) = x gm. Then,

Solution strength is expressed as (in %)

= ($\frac{Mass of solute (x)}{Total mass of solution (Solvent + Solute)}$)

= ($\frac{x}{(x + 250)}$)

Given, percentage strength = 12.5%

Hence,

$\frac{12.5}{100} = \frac{x}{(250 + x)}$

$\frac{125}{1000} = \frac{x}{(250 + x)}$

⇒ 1000x - 125x = 31250

⇒ x =  31250 ÷ 875

⇒ x = 35.71 gm

Hence, to mantain 12.5% salt solution strength, we add 35.71gm of salt to 250 mL of water.