2002 Question 17 (2 Viewers)

[cutemouse]

Hello,

Is this question still in the syllabus, as I can't find any reference to it?

"Explain why alkanes and their corresponding alkenes have similar physical properties, but very different chemical properties." 3 marks

Thanks

 

[micuzzo]

the double bond in alkenes makes them more reactive then alkanes...

alkanes and kenes are non polar and have weak dispersion forces <--- these affect phys properties

 

[cutemouse]

I know the answer... But I was wondering if it's in the current Chemistry Syllabus, if anyone knows could they please comment?

Thanks

 

[micuzzo]

lol didnt read question... i cant find it directly in the syllabus but i think u still need to know it considering its info from prelim... success 1 doesn't say anything about it...(the editor usually comments on questions no longer in syl)

hope it helps

 

[Sarah182]

Yes it is in the syllabus, it is in the prac part when you did the test using bromine water and usually cyclohexene and cyclohexane.

Heres the reference:
"identify data, plan and perform a fisrt-hand investigation to compare the reactivities of appropiate alkenes with the corresponding alkanes in bromine water"

 

[micuzzo]

Yes it is in the syllabus, it is in the prac part when you did the test using bromine water and usually cyclohexene and cyclohexane.

Heres the reference:
"identify data, plan and perform a fisrt-hand investigation to compare the reactivities of appropiate alkenes with the corresponding alkanes in bromine water"

i think thats differnt

 

[study-freak]

Hello,

Is this question still in the syllabus, as I can't find any reference to it?

"Explain why alkanes and their corresponding alkenes have similar physical properties, but very different chemical properties." 3 marks

Thanks

The prac dotpoint for which students have to compare reactivities of alkenes to corresponding alkanes include the knowledge about why they exhibit different chemical properties(synonym for reactivities). Hence, it is in the syllabus. The physical property part is more of an Year 11 thing. We know that alkanes and alkenes are both straight chain hydrocarbons with weak dispersion forces.
(You need to be careful when you say that something is not in the syllabus. Some things are often implied or assumed.)