Suppose elements `X` and `Y` combine to form two compounds `XY_(2)` and `X_(3)Y_(2)` when 0.1 mole of former weigh `10 g` while 0.05 mole of the latter weigh `9g`. What are the atomc weights of `X` and `Y`.

Options

A. 40,30
B. 60,40
C. 20,30
D. 30,20

Answer

A

Explanation

`X + 2Y rarr XY_(2)`
0.1 mol of `XY_(2) = 10 g`
1 mol of `XY_(2) rarr 100 g`
ii. `3X + 2 Y rarr X_(3) Y_(2)`
0.05 mol of `X_(3)Y_(2) = (9)/(0.05) = 180 g`
` {:( :. X + 2 Y = 100),(3X + 2Y = 180):}] {:(MwXY_(2) = 100),(MwX_(2)Y_(3) = 180):}`
Solve of `X` and `Y`
`X = 40 g`
`Y = 30 g`