Boron has 5 protons and if 5 not

Boron has 5 protons, and if 5 not combined with anything B else, has 5 electrons. Boron 10. 811 Boron has 6 neutrons. 11 atomic mass – 5 protons = 6 neutrons

e- e- e- 5 P+ 6 N e- e- 5 B Boron 10. 811

Each electron shell can hold a maximum number of electrons. Shell 1 st 2 nd 3 rd Max 2 8 8 or 18 2, 8, 8 8 e- 2 e- P+ N

Carbon has 6 electrons. 2 go in the first shell, leaving 4 for the second shell. 2, 8, 8

Sodium has 11 electrons. 2 go in the first shell, 8 go in the second shell, leaving 1 for the third shell. 2, 8, 8

How many electrons are in the outer shell of Oxygen? 2, 8, 8 8 O Oxygen 15. 99 8 P+ 8 N

These outer electrons are VALANCE ELECTRONS. Valance electrons control how an atom interacts with other atoms. 8 O Oxygen 15. 99 8 P+ 8 N

10 Ne Neon 20. 180 13 Al Aluminum 26. 982 7 N Nitrogen 14. 007 11 Na Sodium 22. 990 2, 8, 8

On the next two pages of your notebook, copy down the Periodic Table boxes for the following four elements. Write out how many protons, electrons, and neutrons each have. Draw the elements, and highlight the valance electrons. Lithium (3) 2, 8, 8 Sodium (11) Argon (18) Neon (10)

e- e- e- 5 P+ 6 N e- e- 5 B Boron 10. 811

DSJ 3 + sentences: Do any atoms 14 Si have zero protons, neutrons, or electrons? Silicon If so, which elements. 28. 09 If not, why not? Element of the day: Copy the box, draw the atom (large). Identify the number of protons, neutrons, and electrons. Highlight any valance electrons.

1 H Hydrogen 1. 008

14 P+ 14 N 14 Si Silicon 28. 09

14 P+ 14 N

Dimitri Mendeleev developed the Periodic Table. In 1863 there were 56 known elements. He earned the 1906 Nobel Prize in Chemistry.

Particle Charge Location Proton Positiv Nucleus e Neutro None Nucleus n Electro Negati “Cloud” n ve Mass Abbrev. 1 P+ 1 N 0 e-

PArtrid. Ge Ar is the chemical symbol for Argon Ge is the chemical symbol for Germanium

PArtridge 18 18 P+ Argon 22 N Ar 18 e 39. 95 18 P+ 22 N 8 valance electrons Mass of 40 atomic units