In a chemical equation, what do a downward arrow and an upward arrow respectively indicate?
Answer and explanation
Correct answer: Precipitate and gas
In chemical equations, the downward arrow (↓) indicates a precipitate, an insoluble solid formed from a solution during the reaction. The upward arrow (↑) indicates a gas that is evolved or released. For example, BaSO₄↓ marks a precipitate, while H₂↑ marks liberated hydrogen gas. Therefore, option A gives the correct order. Option B reverses the meanings, and C and D assign symbols that are not represented by these arrows.
Frequently asked questions
What is the correct answer to this question?
Precipitate and gas
Why is this the correct answer?
In chemical equations, the downward arrow (↓) indicates a precipitate, an insoluble solid formed from a solution during the reaction. The upward arrow (↑) indicates a gas that is evolved or released. For example, BaSO₄↓ marks a precipitate, while H₂↑ marks liberated hydrogen gas. Therefore, option A gives the correct order. Option B reverses the meanings, and C and D assign symbols that are not represented by these arrows.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Chemical Reactions and Equations.
