Đáp án:

Câu 4:

(1) $CH_2=CH-CH_2-CH_3$ 

(2) $CH_2=CH-CH(CH_3)-CH_3$ 

(3) $CH\equiv C-CH(CH_3)-CH(CH_3)-CH_3$ 

Câu 5:

Các đồng phân alkyne $C_4H_6$:

$HC\equiv C-CH_2-CH_3$ (but-1-yne)

$CH_3-C\equiv C-CH_3$ (but-2-yne)

Các PTHH:

$HC\equiv C-CH_2-CH_3+2Br_2\to CHBr_2-CBr_2-CH_2-CH_3$ 

$CH_3-C\equiv C-CH_3+2Br_2\to CH_3-CBr_2-CBr_2-CH_3$ 

$CH\equiv C-CH_2-CH_3+2H_2\xrightarrow{{Ni, t^o}} CH_3-CH_2-CH_2-CH_3$ 

$CH_3-C\equiv C-CH_3+2H_2\xrightarrow{{Ni, t^o}} CH_3-CH_2-CH_2-CH_3$ 

$HC\equiv C-CH_2-CH_3+AgNO_3+NH_3\to AgC\equiv C-CH_2-CH_3+NH_4NO_3$