Question

Q21. Reena wants to prepare a solution of solute Z in water and she wants this solution as 1.96% mass by mass percent. Which of the following amounts of the solute is correct for dissolution in 100 g of distilled water? A. 0.5 g B. 48 C: 2 g D. 3.5 g 2 x 100 TO f 192 51​

Answer 1

Answer:

It is C. 2 grams.

Explanation:

Concentration = (mass of solute / mass of solution)*100

Here, we are given 100g of water. solution is nothing but solute + solvent. Here, 100g water is solvent.

Try taking 0.5 grams.

Concentration = 0.5/100.5*100 which is around 0.49. So, A is wrong.

Try taking 48 grams.

Concentration = 48/148*100 which will be 32.43. So B is also wrong.

Try taking 2 grams.

Concentration = 2/102*100 = 1/51*100 which is 1.96%.

So, C is correct.

(Alternative method )

You could estimate it is 2 because 2/100 will be 2%. It is closest to 1.96, ( when compared to other options.) but it is better to do the process. /

Hope it helps :) Mark as brainliest please.