1. Atomic Symbols

2. Revision Which side of the periodic table are metals found?
Which group consists of only gases?
Which group consists of metals so soft that you can cut them with a butter knife?

3. Atomic Symbols Given as one or two letters.
The first letter is ALWAYS a capital, the second letter is ALWAYS lower case.
The chemical symbol is derived from the Latin word for the element, this is why some of the names and symbols don’t match up in English

4. Some examples… English Latin Symbol Lead Plumbum Pb Sodium Natrium Na
Potassium
Kalium K
Gold
Aurum Au
Silver
Argentum Ag
Iron
Ferrum Fe
Tungsten
Wolfram W

5. Atomic Number and Atomic Mass
There are two numbers given on the periodic table, these tell use how many protons, electrons and neutrons are in each atom.

6. REMEMBER Atoms are made up of three particles:
Protons, Neutrons and Electrons.
Protons= +ve charge,
Electrons= -ve charge.
Neutrons= no charge.
Elements have an overall charge of 0 so the number of protons must equal the number of electrons.

7. Atomic Number Atomic Number = The number of protons
And for an element the number of protons will equal the number of electrons.

8. Atomic Mass
Atomic Mass = The number of protons + The number of neutrons
If we subtract the Atomic number from the Atomic mass then we are left with just the number of Neutrons for that element.
Atomic mass-Atomic number= number of neutrons

10. Helium
Protons: 2
Electors: 2
Neutrons: – 2 = = 2

11. Try this one yourself.

12. Potassium
Protons: 19
Electrons: 19
Neutrons: 39.1 – 19 = 20.1 = 20

13. Questions
Calculate the number of protons, neutrons, and electrons for the following: