Question

frdzzz its a question from jee no. 15. plzz solve this one. i need full explanation no shortcut plzz guys its urgent. ​

Answer 1

Answer:

i will opt iii)

Explanation:

GLAD TO ANSWER SUCH A GREAT QUESTION :)

Molar mass of salt = (2 × 23) + 32 + (16 × 4) + x × 18

= 142 + 18x

Na2SO4.xH20 --> Na2SO4.(OH)x (anhydrous)

On heating it will lose water and become anhydrous. 55.9% mass is the mass of water in Na2SO4.xH2O.

Mass by mass% = (mass / molar mass of compound) × 100

mass of water = 18x

55.9 = (18x / 142 + 18x) × 100

55.9(142 + 18x) = 1800x

7937.8 + 1006.2x = 1800x

x = 9.99

x = 10 (approx.)

So, the molecular formula of compound is Na2SO4.10H2O.

@Aish_30