Q32 / 73 · NTA Abhyas (JEE Main) 2020 · Chemistry · Some Basic Concepts of Chemistry

26.8 gm $N a_{2} S O_{4} . n H_{2} O$ contains 12.6 of water here the value of 'n' is?

Correct answer: 7

Solution

N a_{2} S O_{4} . n H_{2} O

Molar mass of this salt

= (142 + 18 n)

Mass of water

= \frac{12.6}{26.8} \times (142 + 18 n)

18 n = \frac{12.6}{26.8} (142 + 18 n)

On solving

n = 7

Hence, the correct answer is 7.

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