Cl Cl H H
Cl C - C -C -C H
H H H H
4 carbons in a line. 1st carbon has 2 Cl's and 1 H;
2nd carbon has 1 Cl and 1 H
3rd carbon has 2 H's
4th carbon has 3 H's
name the backbone : butane for 4 carbons; numbers are carbon number that each subitution for hydrogen is on.
C - C
C - C - C - C- C - C - C- C
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C C C
I did not put in all of the hydrogens in the drawing.
a terminal carbon has three hydrogens and middle carbons have enough H's to give them 4 bonds. The ethyl group is H3C-CH2-; and the methyl group is H3C. The numbers are for the carbon order that the substitute groups are on.
H2 C = C - C= CH2
ene is for a double bond; the numbers are for the placements of the double bonds. Buta means four carbons
1,2- pentadiene: 1,2 pentadiene would not exsist due to molecular bond strain. A molecule must have a least one single bond between two double bonds.
1,3 -pentadiene would be similar to 1,3 butadiene with the 1st and 3rd bonds being double.
1,4-pentadiene and 2,4 also exist.
Penta means 5 carbons in a row.
Numbering is always in the order as being the lowest numbers as possible.