Question

potassium
Selenate contain 35.71% of Selenium is isomorphous with Potassium Sulphate calculate the atomic weight of Selenium where k=32 and s 32​

Answer 1

Answer:

It is given that Potassium sulphate (K2SO4) is amorphous with Potassium selenite(K2SeO4).

Let the atomic weight of the Selenium be “a” g.

So, the molecular weight of the Potassium selenate,

= [39*2 + a + 16*4]

= [142 + a]  

Therefore,

(142 + a) g of K2SeO4 contains = “a” g of Se

So, 100 g of K2SeO4 contains = [a/(142+a)] * 100 of Se ….. (i)

% of selenium in potassium selenite is given as = 35.71 …. (ii)

Now,

Equating (i) & (ii), we get

[a/(142+a)] * 100 = 35.71

⇒ 100a = 5070.82 + 35.71a

⇒ 64.29a = 5070.82

⇒ a = 78.87 g

Thus, the atomic weight of selenium is 78.87 g.