A science class is learning about exothermic reactions, which are reactions that transform chemical energy into heat. The students combine substance X and substance Y in a beaker. A chemical reaction between X and Y creates new substance Z. How could the students tell whether the reaction is exothermic?
A. They could measure the change in mass of substance X and substance Y using a balance.
B. They could measure the increase in temperature of the mixed substances using a thermometer.
C. They could measure how long the chemical reaction lasts using a stopwatch.
D. They could measure the volume of substance Z using a graduated cylinder.

The students could tell whether the reaction is exothermic by measure the increase in temperature of the mixed substances using a thermometer.

What is exothermic reactions?

Those reactions which produces heat in the form of energy is known as exothermic reaction.

So to tell whether the reaction is exothermic in nature student should measure the temperature of the reaction beaker befor adding the reactants and after the mixing of reactants.

They could measure the change in mass of substance X and substance Y using a balance, how long the chemical reaction lasts using a stopwatch and volume of substance Z using a graduated cylinder are not considered as they have relation with heat.

Hence student could measure the increase in temperature of the mixed substances using a thermometer.

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https://brainly.com/question/972207

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