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Chemical Reactions and Equations — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceChemical Reactions and Equations1 Mark
MCQ
Complete the missing components/ variables given as x  in the following reactions:

$\text{CaCO}_3​(\text{s})\xrightarrow{\text{x}}\text{​CaO}(\text{s})+\text{CO}_2​(\text{g})$

  • A
    x = Heat
  • B
    x = Catalyst
  • C
    x = O2​
  • D
    None of these
✓

Answer

  1. x = Heat

Explanation:

Calcium carbonate on heating decomposes to form calcium oxide (quick lime) and carbon dioxide.

The equation for this thermal decomposition reaction can be written as:

$\text{CaCO}_3​\xrightarrow{\text{heat}}\text{CaO}+\text{CO}_2​$

Therefore, x in the above reaction is heat.

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