Copper is added to a solution of nitric acid. the solution becomes hot and changes from colorless to dark blue. what is the best explanation for the change in temperature?

When copper is added to a solution of nitric acid, their chemical reaction produces heat.

Explanation:

During the reaction between copper an d nitric acid, the copper metal is oxidised to form copper(ii) ion, by nitrate ion. Then this is converted into notrogen oxide gas. As, a result of this conversion, there is a binding of copper(ii) ion with water molecules of number 6. As a result of this, the copper metal will turn into a solution which is blue and a gas of brown color is obtained.

Thus when copper is added to nitric aci, there is a change in the temperature. The chemical reaction that takes place between Copper and Nitric acid solution generates heat. This process is an exotermic.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.