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JEE Main
Exam
JEE Main
Subject
Chemistry
Chapter
Redox Reactions

JEE Main · Chemistry · Redox Reactions

1g ~of an impure sample of magnesium carbonate (containing no...

1g1g~of an impure sample of magnesium carbonate (containing no thermally decomposable impurities) on complete thermal decomposition gave~0.44g0 . 44g& of carbon dioxide gas. The percentage of impurity in the sample is

Options

  1. A00 %
  2. B4.44 . 4 %
  3. C1616 %
  4. D8.48 . 4 %

Correct answer

C. 1616 %

Step-by-step solution

Consider,

MgCO3→MgO+CO2↑{MgCO}_{3} \to MgO + {CO}_{2} ↑

MgCO3{MgCO}_{3}:~\left(1 \times 24\right) + \left(1 \times 12\right) + \left(3 \times 16\right) = 84g</p><p></p><p>{CO}_{2}: </p><p>(1×12)+(2×16)=44g:~</p><p>\left(1 \times 12\right) + \left(2 \times 16\right) = 44g

100100 %~pure 84g84g~MgCO3{MgCO}_{3} on heating gives 44g44g~CO2{CO}_{2}

Given that~1g1g ~of MgCO3{MgCO}_{3}~on heating gives 0.44g0 . 44g~CO2{CO}_{2}

Therefore, 84g84g~MgCO3{MgCO}_{3}~sample on heating gives 36.96g36 . 96g~CO2{CO}_{2}

Percentage of purity of the sample =~36.96gofCO244gofCO2×100\dfrac{36 . 96gof{CO}_{2}}{44gof{CO}_{2}} \times 100 % = 84 %

Percentage of impurity =~1616 %

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