Question

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2.10 homework/exit ticket review
lewis electron dot diagrams
draw the electron dot diagram for the following
carbon:
chlorine:
nitrogen
helium
hydrogen
calcium
strontium
lewis structures
write the element symbol.
locate element in the p. table
ex) carbon is in the 4th group, so it has 4 valence electrons.
starting at the right, draw 4 electrons, or dots, counter - clockwise around the element symbol

Explanation:

Step1: Determine valence electrons for carbon

Carbon is in group 14 of the periodic table, so it has 4 valence electrons. We write the symbol C and place 4 dots around it, starting from the right and going counter - clockwise. So the Lewis electron - dot diagram for carbon is: C with 4 dots (one on each side).

Step2: Determine valence electrons for chlorine

Chlorine is in group 17 of the periodic table, so it has 7 valence electrons. We write the symbol Cl and place 7 dots around it. The Lewis electron - dot diagram for chlorine is: Cl with 7 dots (2 on top, 2 on the left, 2 on the bottom and 1 on the right).

Step3: Determine valence electrons for nitrogen

Nitrogen is in group 15 of the periodic table, so it has 5 valence electrons. We write the symbol N and place 5 dots around it. The Lewis electron - dot diagram for nitrogen is: N with 5 dots (2 on top, 1 on the left, 1 on the bottom and 1 on the right).

Step4: Determine valence electrons for helium

Helium is in group 18 and has 2 valence electrons. We write the symbol He and place 2 dots around it. The Lewis electron - dot diagram for helium is: He with 2 dots on top.

Step5: Determine valence electrons for hydrogen

Hydrogen is in group 1 and has 1 valence electron. We write the symbol H and place 1 dot next to it. The Lewis electron - dot diagram for hydrogen is: H with 1 dot.

Step6: Determine valence electrons for calcium

Calcium is in group 2 and has 2 valence electrons. We write the symbol Ca and place 2 dots around it. The Lewis electron - dot diagram for calcium is: Ca with 2 dots (one on top and one on the bottom).

Step7: Determine valence electrons for strontium

Strontium is in group 2 and has 2 valence electrons. We write the symbol Sr and place 2 dots around it. The Lewis electron - dot diagram for strontium is: Sr with 2 dots (one on top and one on the bottom).

Answer:

Carbon: C with 4 dots (one on each side)
Chlorine: Cl with 7 dots (2 on top, 2 on the left, 2 on the bottom and 1 on the right)
Nitrogen: N with 5 dots (2 on top, 1 on the left, 1 on the bottom and 1 on the right)
Helium: He with 2 dots on top
Hydrogen: H with 1 dot
Calcium: Ca with 2 dots (one on top and one on the bottom)
Strontium: Sr with 2 dots (one on top and one on the bottom)