Question

Examples of balancing chemical equation of 7th class......pls

Answer 1

let's take the example of the reaction of hydrogen and oxygen to form water(H2O).
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so,
H2+ O2 = H2O

Now in balancing a chemical reaction we have to keep it in mind that the number of particles in one side should be equal to the number of particle and Other Side.

here in the above reaction if you see that
oxygen molecule has 2 oxygen atom in reaction inside and on products side oxygen molecule has only one atom so now we have to balanced equation by placing there also to oxygen atoms.

H2+ O2 = 2H2O

so here I have put two over H2O which makes the two oxygen molecule but here we comes to see that hydrogen molecule in product size become 4sho and reactance it also should be 4 so we put for Molecular soon reaction side.

which can be done by multiplying two over H2

2H2+ O2 = 2H2O.