Comprehension # 1
Potash is any potassium mineral that is used for its potassium content. Most of the potash produced in the United States goes into fertilizer. The major sources of potash are potassium choride `(KCI)` and potassium sulphate `(K_(2)SO_(4))`. Potash production is often reported as the potassium oxide `(K_(2)O)` equivalent or the amount of `K_(2)O` that could be made from a given mineral. `KCI` cost `Rs 50 per kg`
What mass `("in kg")` of `K_(2)O` contains the same number of moles of `K` atoms as `1.00 kg KCI` ?

Answer

A, C

Explanation

Molecular mass of KCl `=39 + 35.5 = 74.5`g
74.5 g of KCl=1 mole atoms of K
1000 g of KCl `=(1 xx 1000)/74.5 = 13.42` mole atoms of K
Now, molecule mass of `K_(2)O = 39 xx 2 + 16 = 94`g
2 mol atoms of K in `K_(2)O` weigh = 94 g
13.42 mol atoms of K in `K_(2)O` weigh `=94/2 xx 13.42 = 631 g = 0.631 `kg