Question
Which of the following reactions represent a chemical change?
A. Heating a solid ammonium chloride in a test tube
B. Putting ink on a filter paper
C. Burning a candle in air
D. Adding sodium chloride in water
A. Heating a solid ammonium chloride in a test tube
B. Putting ink on a filter paper
C. Burning a candle in air
D. Adding sodium chloride in water
Answers
GPT-4o mini
To determine which of the reactions represent a chemical change, let's analyze each option:
A. **Heating a solid ammonium chloride in a test tube** - This typically does not represent a chemical change. Ammonium chloride can sublime upon heating, changing from solid to gas (ammonia and hydrogen chloride), but it does not result in a new substance.
B. **Putting ink on a filter paper** - This represents a physical change. The ink spreads on the filter paper, but the chemical composition of the ink doesn’t change.
C. **Burning a candle in air** - This represents a chemical change. When a candle burns, the wax (a hydrocarbon) reacts with oxygen in the air, producing carbon dioxide, water vapor, and heat.
D. **Adding sodium chloride in water** - This is a physical change. Sodium chloride (table salt) dissolves in water, but it does not change chemically; it remains sodium and chloride ions in solution.
Based on this analysis, the reaction that represents a chemical change is:
**C. Burning a candle in air.**
A. **Heating a solid ammonium chloride in a test tube** - This typically does not represent a chemical change. Ammonium chloride can sublime upon heating, changing from solid to gas (ammonia and hydrogen chloride), but it does not result in a new substance.
B. **Putting ink on a filter paper** - This represents a physical change. The ink spreads on the filter paper, but the chemical composition of the ink doesn’t change.
C. **Burning a candle in air** - This represents a chemical change. When a candle burns, the wax (a hydrocarbon) reacts with oxygen in the air, producing carbon dioxide, water vapor, and heat.
D. **Adding sodium chloride in water** - This is a physical change. Sodium chloride (table salt) dissolves in water, but it does not change chemically; it remains sodium and chloride ions in solution.
Based on this analysis, the reaction that represents a chemical change is:
**C. Burning a candle in air.**