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प्रश्न
Write three steps of writing chemical equations with example?
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उत्तर
- Step I: Write the chemical equation:
For example, \[\ce{H2S2O_{7(l)} + H2O_{(l)} -> H2SO_{4(l)}}\] - Step II: Compare the number of atoms of the various elements present on the two sides of the equation.
Reactants (Left side) Product (Right side) Element Number of atoms Number of atoms H 4 2 S 2 1 O 8 4 - Step III: Choose the reactant or product having a maximum number of atoms and equalize its atoms on both sides. Equalize the number of atoms of remaining elements in the reactants and products. H2S2O7 has a maximum number of atoms. First balance ‘S’ as it requires a smaller factor.
Number of S atoms In the reactant
(in H2S2O7)In the product
(in H2SO4)Initially 2 1 To balance 2 1 × 2
Apply a factor ‘2’ to the product ‘H2SO4’.
\[\ce{H2S2O_{7(l)} + H2O_{(l)} -> 2H2SO_{4(l)}}\]
Check whether the equation is balanced.
The number of atoms of the elements in the reactants is same as the number of atoms of those elements in the product.
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