Which of the following is a reliable way to observe that a chemical change has occurred when two substances come in contact with one another?(1 point)

Question

Responses

observe a color change
observe a color change

test for the release of heat
test for the release of heat

conduct a test to determine the chemical makeup of the molecules
conduct a test to determine the chemical makeup of the molecules

monitor for the release of a gas
monitor for the release of a gas

Answer 1

All of the options provided can indicate that a chemical change has occurred, but some are more immediate and observable than others.

1. Observe a color change - This is often a reliable indicator of a chemical change.
2. Test for the release of heat - Also indicates a chemical change (an exothermic reaction).
3. Conduct a test to determine the chemical makeup of the molecules - This is more of a confirmatory test rather than an immediate observation.
4. Monitor for the release of a gas - The production of gas is a well-known indicator of a chemical change.

Given these points, while all of them can indicate a chemical change, observing a color change, monitoring for the release of a gas, and testing for the release of heat are more immediate, observable indicators:

Best answers: observe a color change and monitor for the release of a gas.