Use the atom builder interactive to identify each nucleus. Two protons represented as purple spheres and one neutron represented as a white sphere. Two protons represented as purple spheres and four neutrons represented as white spheres. Four protons represented as purple spheres and three neutrons represented as white spheres. One proton represented as a purple sphere and two neutrons represented as white spheres. Four protons represented as purple spheres and two neutrons represented as white spheres. Three protons represented as purple spheres and four neutrons represented as white spheres. Answer Bank

Explanation:

In the first nucleus we are told that there are two protons and one neutron. Let us remember that the mass number = number of protons + number of neutrons.

This implies that, for the first specie the mass number is 3, for the second specie the mass number is 6 and the third specie has a mass number of 7 and so on. The mass number is indicated as a superscript.

The atomic number is the number of protons in the nucleus of the atom and helps us to identify the atom. It is always written as a subscript as shown.

what are the choices?

c is the answer because when something is left after something evaporates that shows the chemical change.