1112

Sodium

Atomic number = Mass Number =

2 - 8 - 1

p+

n

2311

23 protons & neutrons

12 neutrons

In a neutral sodium atom the number of protons (11) = the number of electrons (11)

- 11 protons____________________

4 5

Beryllium

Atomic number = Mass Number =

2 - 2

p+

n

94

9 protons & neutrons

5 neutrons

In a neutral beryllium atom the number of protons (4) = the number of electrons (4)

- 4 protons____________________

7 7

Nitrogen

Atomic number = Mass Number =

2 - 5

p+

n

147

14 protons & neutrons

7 neutrons

In a neutral nitrogen atom the number of protons (7) = the number of electrons (7)

- 7 protons____________________

1616

Sulfur

Atomic number = Mass Number =

2 - 8 - 6

p+

n

3216

32 protons & neutrons

16 neutrons

In a neutral sulfur atomthe number of protons (16) = the number of electrons (16)

- 16 protons____________________

1414

Silicon

Atomic number = Mass Number =

2 - 8 - 4

p+

n

2814

28 protons & neutrons

14 neutrons

In a neutral silicon atom the number of protons (14)= the number of electrons (14)

- 14 protons____________________

1920

Potassium

Atomic number = Mass Number =

2 - 8 - 8- 1

p+

n

3919

39 protons & neutrons

20 neutrons

In a neutral potassium atom the number of protons (19) = the number of electrons (19)

- 19 protons____________________