Question

The solubility of a salt in water at room temperature is 30 g per 100 gm of
water. In the following list, a saturated solution is
A. Solution containing 40 g per 200 g water.
B. Solution containing 50 g per 200 g water.
C. Solution containing 15 g per 50 g water.
D. Solution containing 10 g per 50 g water.

Answer 1

Answer :-

Option.C represents a saturated solution .

Explanation :-

It is given that solubility of the salt at room temperature is 30g per 100g water. This means, 100 g of water will dissolve maximum 30 g of the salt at room temperature.

Now, let's check the options one by one .

For Option (A) :-

200 g of water will dissolve at maximum :-

= (2 × 30) g of salt

= 60 g of salt .

∵ Given mass of salt is 40 grams .

∴ This solution is not saturated .

For Option (B) :-

We have seen above that, 200 g of water can dissolve 60 g of the salt at maximum. Here, given mass of salt is 50 g.

∴ This solution is not saturated .

For Option (C) :-

50 g of water will dissolve at maximum :-

= 30/2

= 15 g of salt

∵ Given mass of salt is also 15 gram.

∴ This solution is saturated ✓ .

For Option (D) :-

We have seen above that, 50 g of water can dissolve 15 g of the salt at maximum. Here, given mass is 10 g.

∴ The solution is not saturated .

Answer 2

Given :-

The solubility of a salt in water at room temperature is 30 g per 100 gm of

water

To Find :-

In the following list, a saturated solution is

Solution :-

C. Solution containing 15 g per 50 g water. ✔

Why?

Let's check one by one

A. 100gm : 30 g : 200 gm : 40 g

100(40) = 30(200)

4000 = 6000 {Which not satisfies}

B. 100 gm : 30 g : 200 gm : 50

100(50) = 30(200)

5000 = 6000 {Which also not satisfies}

C. 100 gm : 30 g : 50 gm : 15 g

100(15) = 30(50)

1500 = 1500 {Satisfies}

D. 100 gm : 30 g : 50 gm : 10 g

100(10) = 30(50)

1000 = 1500 {Which also not satifies}

Hence, Option C is correct