Question

methane gas ($ch_4$) is used as a fuel for gas stoves. when methane gas burns in oxygen gas ($o_2$), it produces carbon dioxide gas ($co_2$) and water vapor ($h_2o$). which model accurately represents this reaction?

Explanation:

Step1: Write balanced reaction

The combustion of methane follows:

$$\text{CH}_4 + 2\text{O}_2 ightarrow \text{CO}_2 + 2\text{H}_2\text{O}$$

Step2: Match to particle model

Count reactants/products: 1 $\text{CH}_4$ (1 black, 4 white), 2 $\text{O}_2$ (4 red, paired as 2 molecules), 1 $\text{CO}_2$ (1 black, 2 red), 2 $\text{H}_2\text{O}$ (2 red, 4 white, paired as 2 molecules). This matches the top-left model.

Answer:

The top-left model (1 methane molecule + 2 oxygen molecules → 1 carbon dioxide molecule + 2 water molecules)