Metals are elements that are generally shiny when smooth and clean
Electrons uniting with electrons of another atom is the cause in this relationship. The effect is a chemical change.
When calcium reacts with water, the temperature changes from 18c to 39c is an exothermic reaction as energy is releasing and increasing the temperature.
<h3>What is an exothermic reaction?</h3>
Exothermic reaction are those reactions in which energy is released when a reaction completes.
An example is burning of wood.
Thus, when calcium reacts with water, the temperature changes from 18c to 39c is an exothermic reaction as energy is releasing and increasing the temperature.
Learn more about exothermic reaction
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