6 molecules of hydrogen (H2) react with 3 molecules of oxygen (O2) to produce some amount of water (H2O).

Question

During this reaction, how many molecules of water (H2O) are produced?

Answer 1

The balanced chemical equation for the reaction of hydrogen gas with oxygen gas to produce water is:

$$2H_2+O_2\to 2H_{2}O$$

From the equation, you can see that 2 molecules of $H_2$ react with 1 molecule of $O_2$ to produce 2 molecules of $H_{2}O$.

Now, if we start with 6 molecules of $H_2$ and 3 molecules of $O_2$:

• From the given $H_2$, 6 molecules can react as follows: $$6H_2\times \frac{1O_2}{2H_2}=3O_2$$ This means you will need 3 molecules of $O_2$ to completely react with 6 molecules of $H_2$.

Using the ratios from the balanced equation, for every 2 $H_2$ molecules that react, 2 $H_{2}O$ molecules are produced. Therefore:

$$6H_2\to 6H_{2}O$$

Thus, the reaction produces 6 molecules of water (H2O) in total.