158.5 g of chloride occupies a volume of 22.4 L at STP. The percentage of chlorine in this chloride is 44.71%. The atomic weight and valency of the element is

Options

A. `88,2`
B. `88,1`
C. `71,2`
D. `71,1`

Answer

A

Explanation

Molecular weight of chloride = 158.5
Let the formula of chloride is `MCI_x`.
Let the equivalent weight of metal M is Y.
Then, molecular weight of `MCI_x = y xx x + x xx 35.5 = 158.5`
Equivalent weight of an element is the weight that combines with 35.5 g of chlorine.
Equivalent weight of ` M= ( 55.29 )/(44.71) xx 35.5 = 44`
`44 xx x + 35.5 xx x = 158.5 implies x = 2`
Atomic weight of element , M = 44 `xx 2= 88`
valency = 2 .
Alternatively, amount of chlorine in chloride
` = 158.5 xx (44.71 )/(100) =70.8 g `
` i.e, (70.8 )/(35.5 ) ~~ 2 mol`
` therefore ` Atomic weight of element M= 158.5 - 70.8=87.6 `~~88`
Formula is `MCI_x ` valency = 2.