What would likely happen if you were to touch the flask in which an endothermic reaction occurring

The reaction vessel will feel cool

Explanation:

In an endothermic reaction, heat is absorbed by the reaction system from the surrounding. The withdrawal of heat from the surrounding causes the reaction vessel to feel cool.

Hence when an endothermic reaction is going on, the reaction vessel feels cool when touched.

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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