Question

If a sample of pure hydrogen gas is ignited very carefully, the hydrogen burns gently, combining with the oxygen gas of the air to form water vapor. Write the unbalanced chemical equation for this reaction.

Short answer

The balanced chemical equation for the combustion of hydrogen gas with oxygen gas to form water vapor is: \[ 2H_{2} + O_{2} \rightarrow 2H_{2}O \]

Step-by-step solution

Identify the reactants and products

In this reaction, hydrogen (H2) and oxygen (O2) are the reactants, and the product is water vapor (H2O). Step 2: Writing the unbalanced equation

Write the chemical symbols for the reactants and products

Now that we know the reactants and products, we can write the unbalanced chemical equation: \[ H_{2} + O_{2} \rightarrow H_{2}O \] Step 3: Balancing the chemical equation

Adjust the coefficients to balance the equation

Currently, the equation is not balanced because there are two oxygen atoms on the left side of the equation and only one on the right side. To balance the equation, we can adjust the coefficients. Place a 2 in front of H2O: \[ H_{2} + O_{2} \rightarrow 2H_{2}O \] Now we have 2 hydrogen atoms on the left and 4 on the right. To balance the hydrogen atoms, place a 2 in front of H2: \[ 2H_{2} + O_{2} \rightarrow 2H_{2}O \] The balanced equation should look like this: \[ 2H_{2} + O_{2} \rightarrow 2H_{2}O \]