State the number of atoms of oxygen in the reactants and in the products for each of the f...

State the number of atoms of oxygen in the reactants and in the products for each of the following equations:

a. CH4(g) + 2O2(g) CO2(g) + 2H2O(g)

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b. 4P(s) + 5O2(g) → P4O10(s)

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c. 4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(g)

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d. 6CO2(g) + 6H2O(l) → C6H12O6(aq) + 6O2(g)