chemistry structural diagrams?

Question

A. propene
B. 2-butene
C. 2,4-dimethyl-2-pentene
D. 1-butyne

how to draw the structural diagrams....?

Answer 1

CHვCH=CHշ is propene
CHვCH=CHCHვ is 2-butene
CHვC(CHვ)=CHCH(CHვ)շ is 2,4-Dimethyl-2-pentene
C≡C-CHვ is 1-butyne

Answer 2

Can't really draw here, but here some hints:

A. propene = propane (3C) with a C=C double bond
B. 2-butene = butane (4C) with a C=C double bond at the second carbon position.
C. 2,4-dimethyl-2-pentene = start with pentane (5C), place C=C double bond at second carbon position, at second carbon also put a methyl group (CH3), put another methyl group at fourth carbon position.
D. 1-butyne = start with butane (4C), place triple C,C bond at first carbon position, add on excess H at first position.

* -yne ending = alkyne = triple carbon bond.
All is elementary if you use a reference book or some guide, thats all i can do to help.

Answer 3

using ur brains n book as reference

Answer 4

CH2=CH-CH3

CH3-CH=CH-CH3

(CH3)2C=CH-CH(CH3)2

CH*triplebond*C-CH2CH3