1. ATOMS

2. Atom
Smallest part of any element that contains all properties of that element.

3. The center of an atom. It contains two particles: neutron and proton
The center of an atom. It contains two particles: neutron and proton. Has a positive charge.
Nucleus

4. 3 main subatomic particles are the proton, neutron and electron.
THESE particles are SMALLER than an atom.
***LOOK at the difference in size!!! WOW…an electron is SO SMALL!!!

5. Positively charged particle found in the nucleus.
Proton

6. Neutron
Particle in the nucleus of an atom that does not have a charge. It is a neutral particle.

7. Particle orbiting the nucleus of an atom. It has a negative charge.
Electron

8. Valence Electrons – the electrons in the outermost energy level/shell of an atom; they determine how an element will react with other substances.

10. represents the number of protons found in the atom’s nucleus.

11. Protons + Neutrons=Mass Number
The sum of the number of protons and neutrons found in the nucleus of the atom for that element.
Protons + Neutrons=Mass Number

12. Atomic Number 6 C
Carbon
12.011
Symbol
Element Name
Atomic Mass

13. This is what gives the atom a neutral charge.
Number of Protons
Equals
Number of electrons
This is what gives the atom a neutral charge.

14. The average mass of one atom of an element.
ATOMIC MASS
The average mass of one atom of an element.

15. (atomic mass unit)- the SI unit for the masses of particles in an atom.

16. The Big Picture!

17. Neutron
Proton
Electron

18. How many neutrons does an atom contain if its atomic mass is 65 and it contains 30 protons?

19. Protons + Neutrons ? =

20. Protons + Neutrons
Mass Number =

21. What is the smallest part of any element that contains all properties of that element?
Atom

22. What are the particles that are smaller than an atom called?
Subatomic
Particles

23. What are the 3 main subatomic particles that make up an atom?
Proton
Neutron
Electron

24. What is the center of an atom called?
Nucleus

25. What are the two particles found in the nucleus of an atom?
Proton
and
Neutron

26. What type of charge does the nucleus of an atom have?
Positive

27. What is the positively charged particle found in the nucleus?
Proton

28. The subatomic particle that is neutral is the
Neutron

29. What is the negative charged particle that orbits the nucleus of an atom?
Electron

30. Why does the atom have a neutral charge?
The number of protons in the nucleus of an atom equals the number of electrons orbiting the nucleus.

31. How do we determine the number of electrons in an atom?
Number of electrons equals the number of protons.

32. 17 The element chlorine has an atomic number of 17, it has
_____ protons in its nucleus. 17

33. Mass
Number
Practice

34. How many protons does an atom have if its atomic mass is 12 and it has 6 neutrons?

35. What is the mass number if an atom has 2 protons and 2 neutrons?

36. Which element has an mass number of 12 and contains 6 neutrons?