Answer:
the number of protons in an atom

Absolute Dating
AKA. RADIOMETRIC DATING
We can learn about the past by studying the present.
The Principle of Uniformitarianism states that current geological processes are the same processes that were at work in the past. This principle was proposed by Charles Lyell in the 1800's
Absolute Dating
Involves finding the absolute age (actual age) of a rock or fossil.
Elements that emit particles and energy are radioactive.
As radioactive elements emit particles and energy, they form new isotopes or elements.
This statement about matter is true: MATTER IS MADE UP OF ATOMS AND HAS MASS.
Matter is defined as anything that has mass and occupies space. The mass of an object is the measure of the extent to which the object can resist a change in its direction when a force is applied to it. A matter is usually made up of atoms, which is defined as the smallest component of any matter. Therefore matter is made up of atoms and it has mass.
After my research the answer is that they are forms of electromagnetic radiation as far as I know.
A phase change is when matter changes into another form but keeps its properties