Chemical Reactions - Signs of a Reaction

Signs of a Reaction - Temperature Change

An increase or decrease in temperature both indicate that a chemical reaction is occurring. Here the temperature increased when two liquid samples were mixed.

If a thermometer is not available, a change in temperature can be detected by feeling the reaction vessel. If it feels hot, the temperature increased. If it feels cold, the temperature decreased. Since some reactions generate large amounts of heat, you should be very cautious when touching a reaction vessel.

Continue on to perform the experiment.

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