Question

1. draw a diagram: draw a lewis diagram of the oxygen molecule in the space below at left. to check your work, turn on show lewis diagram. draw the correct diagram on the right. practice diagram: o o actual: o o 4. practice: create covalent bonds and stable molecules for the remaining substances. take a snapshot of each completed molecule and add it to your document. draw lewis diagrams for each one. (as above, draw the diagram on your own before checking your work.) nitrogen n n ammonia h n h chlorine cl cl methane h c h h water h o h carbon dioxide o c o formaldehyde h c h h (activity b continued on next page)

Explanation:

Step1: Determine valence electrons of oxygen

Oxygen has 6 valence electrons.

Step2: Draw Lewis diagram for oxygen molecule

The two oxygen atoms share two pairs of electrons to form a double - bond. Each oxygen also has two lone pairs of electrons. The Lewis diagram is: $:O::O:$

Step3: Determine valence electrons for nitrogen

Nitrogen has 5 valence electrons. In $N_2$, the two nitrogen atoms share three pairs of electrons to form a triple - bond and each nitrogen has one lone pair. The Lewis diagram is: $:N:::N:$

Step4: Determine valence electrons for ammonia ($NH_3$)

Nitrogen has 5 valence electrons and hydrogen has 1. Nitrogen forms three single bonds with hydrogen and has one lone pair. The Lewis diagram is: $H - \underset{\overset{\mid}{H}}{N}-H$ with a lone pair on N.

Step5: Determine valence electrons for chlorine

Chlorine has 7 valence electrons. In $Cl_2$, the two chlorine atoms share one pair of electrons and each chlorine has three lone pairs. The Lewis diagram is: $:Cl - Cl:$

Step6: Determine valence electrons for methane ($CH_4$)

Carbon has 4 valence electrons and hydrogen has 1. Carbon forms four single bonds with hydrogen. The Lewis diagram is: $H - \underset{\overset{\mid}{H}}{C}-H$ with hydrogens at the four corners.

Step7: Determine valence electrons for water ($H_2O$)

Oxygen has 6 valence electrons and hydrogen has 1. Oxygen forms two single bonds with hydrogen and has two lone pairs. The Lewis diagram is: $H - O - H$ with two lone pairs on O.

Step8: Determine valence electrons for carbon dioxide ($CO_2$)

Carbon has 4 valence electrons and oxygen has 6. Carbon forms two double - bonds with oxygen. The Lewis diagram is: $O = C = O$

Step9: Determine valence electrons for formaldehyde ($CH_2O$)

Carbon has 4 valence electrons, hydrogen has 1 and oxygen has 6. Carbon forms a double - bond with oxygen and single bonds with two hydrogens. The Lewis diagram is: $H - \underset{\overset{\mid}{H}}{C}=O$

Answer:

Oxygen molecule: $:O::O:$
Nitrogen: $:N:::N:$
Ammonia: $H - \underset{\overset{\mid}{H}}{N}-H$ (with lone pair on N)
Chlorine: $:Cl - Cl:$
Methane: $H - \underset{\overset{\mid}{H}}{C}-H$ (with hydrogens at four corners)
Water: $H - O - H$ (with two lone pairs on O)
Carbon dioxide: $O = C = O$
Formaldehyde: $H - \underset{\overset{\mid}{H}}{C}=O$