Question

please answer it fast I need it urgent

Answer 1

$\bold\red {hello !!}$

$\bold \green{solution}$
:- Metal is divalent metal of carbonate ,since it has +2 charge therefore Carbonate ion has -2 charge .

Let metal is M . then formula of Carbonate =MCO3

MCO3 ---------> MO + CO2

there is 1 : 1 mole ratio between metal Carbonate and carbon dioxide

•°• 2g of metal Carbonate gives 448cc of carbon dioxide at STP

At STP , 22.4L i.e 22400cm³ volume of one mole of gas .

Mole of gas = 448cm³ ( 1mole /22400cm³)

0.02 mole of carbon dioxide (CO2)

•°• moles of metal Carbonate = 0.02

molar mass of metal Carbonate

= 2g /0.02mole = 100

MCO3 = 100 g /mole

molar mass of MCO3 = molar mass of M + molar mass of C + molar mass of O3

100 = M + 12 + 48

M = 40

•°• equivalent weight = 40/2 = 20

$\bold \pink{hence \: 20 \: is \: answer}$

Option (B) is correct option .

________________________________

$\boxed{hope \: it \: helps}$

Answer 2

Divalent metal carbonate means MCO3MCO3 ------->. MO + CO2 1 mol. 22400 cc 2 g. 448 cc 448 cc of CO2 is evolved from 2g of MCO3 22400 cc of CO2 will be evolved from ( 2× 22400)÷448 = 100g of MCO3i.e. 100g is the molecular wt. of the carbonate Then mol. wt. of metal = 100 - (12+3×16){wt. of CO3 2- }=40gEquivalent wt. = Molecular wt. / Valency = 40/2=20