Question

thu 1/29: evidence of chemical change
if a substance starts glowing during a reaction, what evidence of a chemical change is shown?
temperature change
precipitate formation
light emission
sound production

Explanation:

Glowing during a reaction directly corresponds to the release of light, which is a distinct observable sign of a chemical change. The other options do not match the described phenomenon: temperature change relates to heat, precipitate formation is solid formation from solutions, and sound production involves audible vibrations.

Answer:

C. Light emission