Problem 78 - Chemistry: The Central Science

Question

Write a balanced equation for the reaction that occurs in each of the following cases: (a) Chlorine reacts with water. (b) Barium metal is heated in an atmosphere of hydrogen gas. (c) Lithium reacts with sulfur. (d) Fluorine reacts with magnesium metal.

Step-by-Step Solution

Answer

(a) Cl2 + H2O -> 2HClO + 2HCl (b) Ba + H2 -> BaH2 (c) 2Li + S -> Li2S (d) F2 + Mg -> MgF2

Step 1: Identify reactants and products

For this reaction, the reactants are chlorine (Cl2) and water (H2O). The products are hypochlorous acid (HClO) and hydrochloric acid (HCl).

Step 2: Write the unbalanced chemical equation

Now, we can write down the unbalanced equation using the reactants and products. Cl2 + H2O -> HClO + HCl

Step 3: Balance the equation

In order to balance the equation, we need to ensure the number of atoms for each element is the same on both sides of the equation. We can start by balancing the chlorine atoms. Since there are two chlorine atoms in Cl2 molecule and 1 in HCl and 1 in HClO, we need to have 2 molecules of HClO and 2 molecules of HCl: Cl2 + H2O -> 2HClO + 2HCl Now, the equation is balanced. (b) Barium metal is heated in an atmosphere of hydrogen gas

Step 1: Identify reactants and products

For this reaction, the reactants are barium metal (Ba) and hydrogen gas (H2). The product is barium hydride (BaH2).

Step 2: Write the unbalanced chemical equation

Now, we can write down the unbalanced equation using the reactants and products. Ba + H2 -> BaH2

Step 3: Balance the equation

In order to balance the equation, we need to ensure the number of atoms for each element is the same on both sides of the equation. In this case, the equation is already balanced. (c) Lithium reacts with sulfur

Step 1: Identify reactants and products

For this reaction, the reactants are lithium (Li) and sulfur (S). The product is lithium sulfide (Li2S).

Step 2: Write the unbalanced chemical equation

Now, we can write down the unbalanced equation using the reactants and products. Li + S -> Li2S

Step 3: Balance the equation

In order to balance the equation, we need to ensure the number of atoms for each element is the same on both sides of the equation. Since there are two lithium atoms in the Li2S molecule, we need to have 2 Li atoms on the reactant side: 2Li + S -> Li2S Now, the equation is balanced. (d) Fluorine reacts with magnesium metal

Step 1: Identify reactants and products

For this reaction, the reactants are fluorine (F2) and magnesium (Mg). The product is magnesium fluoride (MgF2).

Step 2: Write the unbalanced chemical equation

Now, we can write down the unbalanced equation using the reactants and products. F2 + Mg -> MgF2

Step 3: Balance the equation

In order to balance the equation, we need to ensure the number of atoms for each element is the same on both sides of the equation. In this case, the equation is already balanced.