A metal oxide has the formula `Z_(2)O_(3)`. It can be reduced by hydrogen to give free metal and water. 0.1596 g of the metal requires 6 mg of hydrogen for complete reduction. The atomic mass of the metal is:

Answer

c

Explanation

`Z_(2)O_(3)+3H_(2)(g) to 2Z+3H_(2)O`
`therefore "6g "H_(2)" gives 2 mole Z"`
`therefore 6xx10^(-3)"g "H_(2)" will give 0.002 mole Z"`
`"Number of moles"=("Mass")/("Molar mass")`
`0.002=(0.1596)/("Molar mass")`
`"Molar mass"=(0.1596)/(0.002)=79.8"g mol"^(-1)`