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NISA [10]
3 years ago
12

A scientist is performing an experiment on a powder. Which of the following is a sign that a chemical change has definitely occu

rred during his experiment?
The powder catches on fire.
The powder releases bubbles.
The powder heats up.
The powder breaks apart into smaller particles.
Chemistry
1 answer:
n200080 [17]3 years ago
7 0
The powder catches fire. The rest of the choices pertains to physical changes on the powder. When the powder catches fire a chemical change happens. For example, if the powder is organic, carbon dioxide and water will result during the combustion. 
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