A metal gives gas with an acid but copper does not. What conclusion follows?
Answer and explanation
Correct answer: The first metal is more reactive than hydrogen, while copper is less reactive than hydrogen.
The relevant principle is the metal reactivity series. A metal above hydrogen can displace hydrogen from a dilute acid, producing hydrogen gas; for example, metal + acid can form a salt and H₂. Copper is below hydrogen in the usual school-level reactivity series and generally does not release hydrogen from dilute non-oxidising acids. Thus A follows. The gas is not always carbon dioxide, and the observation does not make copper highly reactive.
Frequently asked questions
What is the correct answer to this question?
The first metal is more reactive than hydrogen, while copper is less reactive than hydrogen.
Why is this the correct answer?
The relevant principle is the metal reactivity series. A metal above hydrogen can displace hydrogen from a dilute acid, producing hydrogen gas; for example, metal + acid can form a salt and H₂. Copper is below hydrogen in the usual school-level reactivity series and generally does not release hydrogen from dilute non-oxidising acids. Thus A follows. The gas is not always carbon dioxide, and the observation does not make copper highly reactive.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
