Write a balanced chemical equation for the reaction of solid potassium with liquid water.

Understanding a chemical reaction begins by recognizing it as a process where substances, known as reactants, transform into entirely different substances called products. This metamorphosis happens through the breaking and forming of chemical bonds, resulting in new substances with different properties. For instance, when solid potassium reacts with liquid water, a chemical reaction occurs that produces two new substances: potassium hydroxide and hydrogen gas. It's essential to note that these reactions follow the law of conservation of mass, which states that the mass of the reactants must equal the mass of the products. For this reason, we must balance chemical equations to ensure that the number of atoms for each element is the same on both sides of the reaction. This balanced equation serves as a recipe for the chemical reaction, detailing the precise amount of reactants needed and products formed.

In the context of a chemical equation, the substances we start with—those that undergo the chemical change—are called reactants. Conversely, the substances produced as a result of the reaction are known as products. In our example exercise, solid potassium (K) and liquid water (H₂O) are the reactants, while potassium hydroxide (KOH) and hydrogen gas (H₂) are the products. It's like a baking recipe where you start with specific ingredients (reactants) such as flour, sugar, and eggs, and end up with a cake (product) after mixing and heating. Similarly, during the reaction of potassium with water, it's crucial to identify the reactants and predict the products correctly to understand the reaction fully. Once the reactants and products are identified, they are then used to write an unbalanced chemical equation, which is the first step in illustrating the chemical process that has occurred.

Stoichiometry is the section of chemistry that pertains to measuring and calculating the quantities of reactants and products involved in chemical reactions. It is the backbone of chemistry because it ensures that equations are balanced, reflecting the conservation of mass. In the reaction between solid potassium and water, stoichiometry helps us determine how much of each reactant is needed to form the desired amount of products without any excess.During the balancing process, coefficients are placed before the chemical formulas to indicate the quantities needed to balance the equation. For example, upon balancing the equation for the reaction between potassium and water, it is determined that two water molecules are needed for each atom of potassium to form two units of potassium hydroxide and one molecule of hydrogen gas. This reflects the stoichiometric relationship between the reactants and products, providing a clear understanding of the reaction's proportions.