Question

show how many valence electrons each of the following elements have using dot diagrams:

1. sulfur:
2. silicon:
3. strontium:
4. helium:

Explanation:

Step1: Determine position of sulfur in periodic table

Sulfur is in group 16. Group number indicates valence - electron number for main - group elements. So sulfur has 6 valence electrons. Dot diagram: place 6 dots around the symbol 'S'.

Step2: Determine position of strontium in periodic table

Strontium is in group 2. So it has 2 valence electrons. Dot diagram: place 2 dots around the symbol 'Sr'.

Step3: Determine position of silicon in periodic table

Silicon is in group 14. So it has 4 valence electrons. Dot diagram: place 4 dots around the symbol 'Si'.

Step4: Determine position of helium in periodic table

Helium is in group 18 (noble gas). It has 2 valence electrons (it has a full outer shell with only 2 electrons as it is in the first period). Dot diagram: place 2 dots around the symbol 'He'.

Answer:

Sulfur: 6 valence electrons, dot - diagram with 6 dots around 'S'
Strontium: 2 valence electrons, dot - diagram with 2 dots around 'Sr'
Silicon: 4 valence electrons, dot - diagram with 4 dots around 'Si'
Helium: 2 valence electrons, dot - diagram with 2 dots around 'He'