: You should be able to write balanced chemical equations for the reactions between acids and metals, including the correct formulae for the salts formed.

To write balanced chemical equations for the reactions between acids and metals, we need to follow certain steps to ensure we include the correct reactants, products, and their respective states of matter. Here’s how to approach this problem:

1. Identify the Reactants

Typically, the reactants will include:

• An acid (for example, hydrochloric acid, HCl)
• A metal (for example, zinc, Zn)

2. Determine the Products

The reaction between an acid and a metal commonly produces:

• A salt (derived from the metal and the anion from the acid)
• Hydrogen gas (H₂)

For instance, when hydrochloric acid reacts with zinc, the products will be:

• Zinc chloride (ZnCl₂) as the salt
• Hydrogen gas (H₂)

3. Write the Unbalanced Equation

The unbalanced chemical equation for the above reaction can be written as: $\text{HCl} + \text{Zn} \rightarrow \text{ZnCl}_{2} + \text{H}_{2}$

4. Balance the Equation

To balance the equation, ensure the number of atoms of each element is the same on both sides.

Starting with:

• Left: 1 H (from HCl), 1 Cl (from HCl), 1 Zn (from Zn)
• Right: 2 Cl (from ZnCl₂), 2 H (from H₂)

We see that the chlorine and hydrogen are unbalanced. To balance it, we can adjust the coefficients: $\text{2 HCl} + \text{Zn} \rightarrow \text{ZnCl}_{2} + \text{H}_{2}$

5. Final Balanced Equation

Now, the balanced equation is: $\text{2 HCl} + \text{Zn} \rightarrow \text{ZnCl}_{2} + \text{H}_{2}$

Final Answer

The balanced chemical equation for the reaction between hydrochloric acid and zinc is: $\text{2 HCl} + \text{Zn} \rightarrow \text{ZnCl}_{2} + \text{H}_{2}$