Translate the following chemical equation into a sentence: $$\mathrm{CH}_{4}(g)+2 \mathrm{O}_{2}(g) \rightarrow \mathrm{CO}_{2}(g)+2 \mathrm{H}_{2} \mathrm{O}(g)$$

Chemical reactions are the processes in which substances, known as reactants, transform into new substances called products. During a chemical reaction, the atoms and molecules of reactants interact, often resulting in a change of physical properties or the release or absorption of energy. One classic example of a chemical reaction is the combustion of methane in the presence of oxygen to produce carbon dioxide and water vapor.

Each chemical reaction is represented by a chemical equation, which uses chemical formulas to depict the transformation. In our example, \(\mathrm{CH}_{4}(g) + 2\mathrm{O}_{2}(g) \rightarrow \mathrm{CO}_{2}(g) + 2\mathrm{H}_{2}\mathrm{O}(g)\), methane (\(\mathrm{CH}_{4}\)) reacts with oxygen (\(\mathrm{O}_{2}\)) to produce carbon dioxide (\(\mathrm{CO}_{2}\)) and water vapor (\(\mathrm{H}_{2}\mathrm{O}\)). It's important to grasp the concept of chemical reactions to understand how different substances can combine and result in entirely new products with different properties.

Balancing chemical equations is a key part of chemistry that ensures the law of conservation of mass is respected. In simple terms, this means what goes into the reaction must come out of it; no atoms are lost or gained, only rearranged. The numbers in front of the chemical formulas in equations are called coefficients, and they indicate the proportion of molecules or atoms involved in the reaction.

To balance an equation, we adjust these coefficients, so the number of atoms for each element is the same on both sides of the equation. For the reaction given, methane reaction with oxygen, we place a coefficient of 2 before oxygen gas to show that two oxygen molecules are required for every one methane molecule. Similarly, we also have carbon dioxide and two water vapor molecules as the products. This demonstrates a balanced reaction where the number of atoms of each element balances out on both sides of the equation.

Reactants are the starting materials in a chemical reaction that undergo chemical changes to form new substances. The products, on the other hand, are the end result of the reaction. Identifying reactants and products is critical for understanding and communicating what happens during a chemical reaction.

In our methane combustion example, the reactants are methane (\(\mathrm{CH}_{4}\)) and oxygen (\(\mathrm{O}_{2}\)), which are the substances undergoing the change. The products, which result from this reaction, are carbon dioxide (\(\mathrm{CO}_{2}\)) and water vapor (\(\mathrm{H}_{2}\mathrm{O}\)). When translating chemical equations to sentences, as in Step 3 of the solution, it's crucial to convey the reactants converting into products through the reaction process with correct stoichiometry, the study of the quantitative relationships between the amounts of reactants used and products formed by a chemical reaction, reflected in our balanced chemical equation.