Dilute hydrochloric acid reacts with iron fillings .

Explanation

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this reaction are dilute hydrochloric acid (HCl) and iron fillings (Fe).

2. **Write the Chemical Equation**:
- The chemical equation for the reaction between iron and hydrochloric acid can be written as:
\[
...