Explain what it means for a reaction to be endothermic and what would happen to the temperature recorded by a thermometer in an endothermic reaction.

1. For a endothermic reaction , energy is absorbed

2. The temperature recorded by a thermometer in an endothermic reaction would be reduced.

Explanation:

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and which is difference between energy of products and energy of reactants come out to be positive.  The temperature of the surroundings will decrease.

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and which is difference between energy of products and energy of reactants comes out to be negative.The temperature of the surroundings will increase.

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation:

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