làm giúp em bài 5 với mọi người

`a)`

Alkine: `C_nH_{2n-2}`

`M=14n-2=20.2=40`

`->n=3`

`->C_3H_4`

`b)`

Alkine: `C_nH_{2n-2}`

`\%C={12n}/{14n-2}.100=90`

`->n=3`

`->C_3H_4`

`c)`

Alkine: `C_nH_{2n-2}`

`C_nH_{2n-2}+2H_2` $\xrightarrow{t^o,Ni}$ `C_nH_{2n+2}`

`n_{C_nH_{2n-2}}=n_{C_nH_{2n+2}}`

`<=>4/{14n-2}={4,4}/{14n+2}`

`->n=3`

`->C_3H_4`

`d)`

Alkine: `C_nH_{2n-2}`

`n_{Br_2}={32}/{160}=0,2(mol)`

`2Br_2+C_nH_{2n-2}->C_nH_{2n-2}Br_4`

`0,2->0,1(mol)`

`M_{C_nH_{2n-2}}=14n-2={5,4}/{0,1}=54`

`->n=4`

`->C_4H_6`

`e)`

Alkine: `C_nH_{2n-2}`

`C_nH_{2n-2}` $\xrightarrow{+AgNO_3/NH_3}$ `C_nH_{2n-3}Ag`

`n_{C_nH_{2n-2}}=n_{C_nH_{2n-3}Ag}`

`<=>{6,8}/{14n-2}={17,5}/{14n+105}`

`->n=5`

`->C_5H_8`

`f)`

Alkine: `C_nH_{2n-2}`

`C_nH_{2n-2}` $\xrightarrow{+AgNO_3/NH_3}$ `C_nH_{2n-3}Ag`

`n_{C_nH_{2n-2}}=n_{C_nH_{2n-3}Ag}`

`<=>{5,2}/{14n-2}={48}/{14n+105}`

`->n=2`

`->C_2H_2`

`->C_5H_8`