In an unknown reaction, the colour changes, heat is released, and a gas forms. What is the most suitable conclusion?
Answer and explanation
Correct answer: There is a strong possibility of a chemical reaction
The governing concept is identifying evidence of a chemical reaction. A colour change, release of heat, and formation of a gas are observable indicators that new substances may have formed. Because several indicators occur together, option A is the strongest conclusion. A physical change usually does not produce such combined evidence, while options C and D contradict the observations.
Frequently asked questions
What is the correct answer to this question?
There is a strong possibility of a chemical reaction
Why is this the correct answer?
The governing concept is identifying evidence of a chemical reaction. A colour change, release of heat, and formation of a gas are observable indicators that new substances may have formed. Because several indicators occur together, option A is the strongest conclusion. A physical change usually does not produce such combined evidence, while options C and D contradict the observations.
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.
