Question

element | reactant | product
h | 4 | 4
o | 2 | 2

are both sides of the equation equal?
does this equation follow the law of conservation of matter?

Explanation:

Step1: Count H atoms (reactants)

Reactants: $2\mathrm{H_2}$ → $2 \times 2 = 4$ H atoms

Step2: Count O atoms (reactants)

Reactants: $\mathrm{O_2}$ → $2$ O atoms

Step3: Count H atoms (products)

Products: $2\mathrm{H_2O}$ → $2 \times 2 = 4$ H atoms

Step4: Count O atoms (products)

Products: $2\mathrm{H_2O}$ → $2 \times 1 = 2$ O atoms

Step5: Compare reactant/product counts

For H: $4 = 4$; For O: $2 = 2$

Step6: Evaluate conservation of matter

Law requires equal atom counts on both sides.

Answer:

1. Yes, both sides of the equation are equal (4 H atoms and 2 O atoms on each side).
2. Yes, this equation follows the law of conservation of matter, as the number of each type of atom is conserved between reactants and products.

The balanced chemical equation is: $2\mathrm{H_2} + \mathrm{O_2}
ightarrow 2\mathrm{H_2O}$