Question

metal oxide has 75% metal. If vapour density of metal chloride is 89 then atomic weight of metal will be 1)59.5 2)72 3)24 4)48

Answer 1

An oxide /ˈɒksaɪd/ is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– atom. Metal oxides thus typically contain an anion of oxygen in the oxidation state of −2

Answer 2

Answer: 3)24

Explanation: Molar mass of $MCl_x=2\times {\text [vapor density}}$

Molar mass of $MCl_x$ = 2\times 89 = 178 g

$M+x\times 35.5 g/mol=178$    (1)

Given : metal oxide has 75% metal.

Thu formula of metal oxide = $M_2O_x$

${\text {percentage of metal}}=\frac{2M}{2M+16x}=0.75$

$0.5\times M=12x$

$M=24x$   (2)

Solving (1) and (2)

$x=3$

thus atomic mass of metal is $24\times 3=72g$