What reacts with hydrochloric acid to give hydrogen?

Options

A. Ammonia
B. Iron
C. Silver
D. Sodium hydroxide

Explanation

To determine what reacts with hydrochloric acid (HCl) to produce hydrogen gas (H2), we can follow these steps:

### Step 1: Understand the Reactivity of Metals
- Metals that are more reactive than hydrogen can displace hydrogen from hydrochloric acid. This means they can react with HCl to produce hydrogen gas.

### Step 2: Identify Reactive Metals
- From the reactivity series of metals, we know that metals like zinc (Zn), iron (Fe), and magnesium (Mg) are more reactive than hydrogen. Therefore, they can react with hydrochloric acid.

### Step 3: Write the Reaction
- When a reactive metal, such as iron, reacts with hydrochloric acid, the reaction can be represented as:

\[ \text{Metal} + \text{HCl} \rightarrow \text{Metal Chloride} + \text{H}_2 \]

- For example, if we take iron (Fe):

\[ \text{Fe} + 2 \text{HCl} \rightarrow \text{FeCl}_2 + \text{H}_2 \uparrow \]

### Step 4: Conclusion
- Therefore, metals like iron and zinc react with hydrochloric acid to produce hydrogen gas. Silver (Ag), being less reactive than hydrogen, does not react with hydrochloric acid to produce hydrogen.

### Final Answer
- Metals such as iron (Fe) and zinc (Zn) react with hydrochloric acid to give hydrogen gas.

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