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Maharashtra State BoardSSC (English Medium) 10th Standard

Write three steps of writing chemical equations with example?

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Question

Write three steps of writing chemical equations with example?

Answer in Brief
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Solution

  1. Step I: Write the chemical equation:
    For example, \[\ce{H2S2O_{7(l)} + H2O_{(l)} -> H2SO_{4(l)}}\]
  2. 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
  3. 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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Chapter 3: Chemical reactions and equations - Answer the Following [Page 35]

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SCERT Maharashtra Science and Technology Part 1 [English] Standard 10 Maharashtra State Board
Chapter 3 Chemical reactions and equations
Answer the Following | Q 2. | Page 35

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