Element X reacts with oxygen to produce a pure sample of `X_(2)O_(3)`. In an experiment it is found that `1.00g` of X produces `1.16g" of "X_(2)O_(3)`. Calculate the atomic weight of X. (Atomic weight of oxygen, `16.0 gmol^(-1)`).

Options

A. 67
B. `100.2`
C. 125
D. 150

Answer

D

Explanation

The mass of O atoms `= 1. 16 - 1.00 = 0 .16 g`
Number of moles of atom `= ( 0. 16)/(116) = 0. 01`
In `X _(2) O _(3) , ("No. of moles of X")/("No . of moles of O")= (2)/(3)`
Number of moles of `X = (2)/(3) xx 0. 01 = ( 0. 02)/(3) = 0. 00666`
Atomic weight of , `X = ( "massing")/("no . of moles") = (1. 0)/( 0. 000666) = 150`