Question

question 2

when an acid reacts with a metal, what is one of the usual products?

none of these
water
salt
hydrogen gas
carbon dioxide

Explanation:

🆕 New Concept Discovered: Acid-Metal Reactions
Metals displace hydrogen from acids to release gas

Step 1: Analyze the reaction type

When a reactive metal reacts with an acid, a single displacement reaction occurs. The general word equation for this chemical reaction is:

$$ \text{Metal} + \text{Acid} ightarrow \text{Salt} + \text{Hydrogen gas} $$

Step 2: Identify the products

• Salt: The metal replaces the hydrogen in the acid to form an ionic compound (a salt).
• Hydrogen gas (\(\text{H}_2\)): The displaced hydrogen atoms pair up and are released as a gas.

Looking at the given options:

• none of these
• water
• salt
• hydrogen gas
• carbon dioxide

Both "salt" and "hydrogen gas" are usual products of this reaction. However, in standard introductory chemistry, the release of hydrogen gas (often observed as bubbles or effervescence) is the characteristic, highly visible product used to identify this specific type of reaction.

Let's look at a classic example:

$$ \text{Zn (s)} + 2\text{HCl (aq)} ightarrow \text{ZnCl}_2\text{ (aq)} + \text{H}_2\text{ (g)} $$

Here, zinc chloride is the salt, and hydrogen gas is released. Since both "salt" and "hydrogen gas" are listed as separate options, "hydrogen gas" is the most distinctive and commonly tested product representing the gaseous release in acid-metal reactions.

Answer:

hydrogen gas