Question

Complete the following synthesis reactions by writing both the word and chemical equation for each: a. potassium \(+\) chlorine \(\longrightarrow\) _____ b. hydrogen \(+\) iodine \(\longrightarrow\) _____ c. magnesium \(+\) oxygen \(\longrightarrow\) _____

Short answer

(a) Potassium + Chlorine → Potassium chloride (2K + Cl_2 → 2KCl)(b) Hydrogen + Iodine → Hydrogen iodide (H_2 + I_2 → 2HI)(c) Magnesium + Oxygen → Magnesium oxide (2Mg + O_2 → 2MgO)

Step-by-step solution

Write the reactants for reaction (a)

Identify the reactants: potassium (K) and chlorine (Cl). These react to form a compound of potassium chloride.

Write the word equation for reaction (a)

Combine the names of the reactants and products to form the word equation: Potassium + Chlorine → Potassium chloride.

Write the balanced chemical equation for reaction (a)

Potassium (K) and chlorine (Cl_2) react to form potassium chloride (KCl). Make sure the equation is balanced: 2K + Cl_2 → 2KCl.

Write the reactants for reaction (b)

Identify the reactants: hydrogen (H) and iodine (I). These react to form a compound of hydrogen iodide.

Write the word equation for reaction (b)

Combine the names of the reactants and products to form the word equation: Hydrogen + Iodine → Hydrogen iodide.

Write the balanced chemical equation for reaction (b)

Hydrogen (H_2) and iodine (I_2) react to form hydrogen iodide (HI). Make sure the equation is balanced: H_2 + I_2 → 2HI.

Write the reactants for reaction (c)

Identify the reactants: magnesium (Mg) and oxygen (O). These react to form a compound of magnesium oxide.

Write the word equation for reaction (c)

Combine the names of the reactants and products to form the word equation: Magnesium + Oxygen → Magnesium oxide.

Write the balanced chemical equation for reaction (c)

Magnesium (Mg) and oxygen (O_2) react to form magnesium oxide (MgO). Make sure the equation is balanced: 2Mg + O_2 → 2MgO.

Key concepts

word equations

In chemistry, a word equation is a way to represent a chemical reaction using the names of the reactants and products. It's the simplest way to describe what is happening during the reaction. For example, in the reaction between potassium and chlorine, the word equation would be: Potassium + Chlorine → Potassium chloride.
This format helps you quickly understand the elements involved and the products formed. It doesn’t show any details about the quantities or the molecular structure, but it’s a great starting point for further analysis.

balanced chemical equations

Balanced chemical equations are crucial for understanding the exact proportions of reactants and products in a reaction. In a balanced equation, the number of atoms of each element is the same on both sides. For example, in the synthesis of potassium chloride:
2K + Cl_2 → 2KCl. This equation shows that 2 atoms of potassium react with 1 molecule of chlorine (which has 2 atoms) to form 2 molecules of potassium chloride.
Balancing is important because it adheres to the Law of Conservation of Mass, meaning matter is neither created nor destroyed in a chemical reaction. It ensures you accurately represent the quantities involved.

reactants and products

In any chemical reaction, you start with **reactants**, which are the substances that react with one another. For example, in the reaction:
Magnesium + Oxygen → Magnesium oxide,
Magnesium (Mg) and Oxygen (O_2) are the reactants.
The **products** are the new substances formed as a result of the reaction. In this case, the product is Magnesium oxide (MgO).
Understanding the difference between reactants and products is essential for studying chemical reactions. This knowledge helps you identify what you start with and what you get at the end of the reaction. It also helps you figure out how to balance the equation accurately by ensuring that the same number of atoms of each element is present on both sides of the equation.