what are two major branches of natural science?

2-How do matter and energy differ ?  

3- Define an atom and molecule

4-What are tue three basic subatomic particles?

What is ionization?

6-What is the formula used to dtermine the maximum number of electrons that can be contained in a giving shell? How many electrons can be contained  in the N shell?

7- The periodic table of elements arranges the elements into periods and group. How are the elements similar within each period and within each group ?

8- How do radiationa differs along the electromagnetic specptrum?

9- list 5 types of energy 

10-For electromagnetic radiation what is the relationship between frequency and wavelength and between frequency photon  energy  

11-List five properties of Xrays