Home
Class 11
CHEMISTRY
20.0 g of a magnesium carbonate sample d...

20.0 g of a magnesium carbonate sample decomposes on heating to give carbon dioxide and 8.0 g magnesium oxide. What will be the percentage purity of magnesium carbonate in the sample ? (At. Wt of Mg = 24)

A

96

B

84

C

60

D

75

Text Solution

Verified by Experts

The correct Answer is:
B
`underset(84g)(MgCO_(3))overset(heat)(rarr)underset(40g)(MgO)+CO_(2)`
84 g of `MgCO_(3)` yield upon heating MgO = 40 g
20 g of `MgCO_(3)` yield upon heating `MgO=((40g)xx(20g))/((84g))`
`=9.52g`
Weight of MgO actually formed = 8.0g
% purity of `MgCO_(3)=((8.0g))/((9.52g))xx100=84%`.
Promotional Banner

Topper's Solved these Questions

  • MOLE CONCEPT

    DINESH PUBLICATION|Exercise JEE (Main)|31 Videos

  • MOLE CONCEPT

    DINESH PUBLICATION|Exercise Comprehension|11 Videos

  • MOLE CONCEPT

    DINESH PUBLICATION|Exercise Problems for practice|133 Videos

  • HYDROGEN

    DINESH PUBLICATION|Exercise LONG|1 Videos

  • NOMENCLATURE OF ORGANIC COMPOUNDS

    DINESH PUBLICATION|Exercise MCQs|13 Videos

Similar Questions

Explore conceptually related problems

20.0 g of magnesium carbonate sample decomposes on heating to give carbon dioxide and 8.0 g of magnesium oxide. What will be the percentage purity of magnesium carbonate in the sample?

20.0 g of a magnesium carbonate sample decomposes on heating to give carbon dioxide and 8.0 g magnesium oxide. What be the percentage purity of magnsesium carbonate in the sample?

Metal carbonates decompose on heating to give metal oxide and carbon dioxide. Which of the metal carbonates is most stable thermally?

2.5 g of an impure sample of sodium bicarbonate when heated strongly gave 300 ml of carbon dioxide measured at 27^(@) C and 760 mm pressure. Calculate the percentage purity of the sample

1 gm of a mixture of calcium carbonate and magnesium carbonate gave on ignition 240 mL of carbon dioxide at S.T.P. What is the percentage composition of the mixture ?

DINESH PUBLICATION-MOLE CONCEPT-Competitive (MCQ)
  1. Volume occupied by one molecule of water (density "1 g cm"^(-3)) is :

    Text Solution

    |

  2. 10 g of hydrogen and 64 g of oxygen were filled in a steel vessel and ...

    Text Solution

    |

  3. How many moles of iodine are liberated when 1 mole of potassium dichro...

    Text Solution

    |

  4. The number of atoms in 0.1 mole of triatomic gas is :

    Text Solution

    |

  5. If 1.5 moles of oxygen combine with Al to form Al(2)O(3). The mass of ...

    Text Solution

    |

  6. Which has maximum number of molecules among the following ?

    Text Solution

    |

  7. How many grams of concentrated nitric acid solution should be used to ...

    Text Solution

    |

  8. 1.0 g of magnesium is burnt with 0.56 g of O(2) in a closed vessel. Wh...

    Text Solution

    |

  9. When 22.4 litres of H(2)(g) is mixied with 11.2 litres of Cl(2)(g), ea...

    Text Solution

    |

  10. Mole fraction of solute in a 2.0 molal aqueous solution is :

    Text Solution

    |

  11. What is the mass of the precipitate formed when 50 mL of 16.9 % soluti...

    Text Solution

    |

  12. The number of water molecules is maximum in :

    Text Solution

    |

  13. What is the mole fraction of the solute in a 1.0 m aqueous solution ?

    Text Solution

    |

  14. 20.0 g of a magnesium carbonate sample decomposes on heating to give c...

    Text Solution

    |

  15. If Avogadro number N(A), is changed from 6.022 xx 10^(23) mol^(-1) to ...

    Text Solution

    |

  16. Which one of the following has maximum number of molecules ?

    Text Solution

    |

  17. The density of 2.0 M solution of a solute is 1.2 g mL^(-1). If the mol...

    Text Solution

    |

  18. Suppose the elements X and Y combine to form two compounds of XY(2) an...

    Text Solution

    |

  19. A solution contains 4 g of NaOH and 16.2 g of water. The mole fraction...

    Text Solution

    |

  20. No. of moles in 100 mg of heptane is …………than those in 10 mg o...

    Text Solution

    |