Carbon exists in different crystalline forms. Some of these forms were recently discovered in soot and are called fullerenes
(i) What name is given to different crystalline forms of the same element?
(ii) Fullerenes dissolve in methylbenzene while the other forms carbon do not. Given that soot is a mixture fullerenes and other solids forms of carbon, describe how crystals of fullerenes can be obtained from soot.
(iii) The relative molecular mass of one of the fullerenes is 720. What is the molecular formula of this fullerene? (C=12.0).
Answer:
i)Allotropes
ii)
- Add soot to methylbenzene, fullerene dissolves. Filter the mixture to remove the residue. Heat the filtrate to make concentrated then cool the solution slowly to get crystals of fullerenes
iii)
12n=720
therefore,
n=#720/12=60#
and molecular formula is #C_60#
ii)
- Add soot to methylbenzene, fullerene dissolves. Filter the mixture to remove the residue. Heat the filtrate to make concentrated then cool the solution slowly to get crystals of fullerenes
iii)
12n=720
therefore,
n=#720/12=60#
and molecular formula is #C_60#
Share To Friends Via:
in an experiment, soap solution was added to three separate samples of water. The table below shows the volumes of the soap solutions required to form lather with #1000cm^3# of each sample of water before and after boiling.
a) Which water sample is likely to be soft? Explain.
(b) Name the cause of change in the volume of soap solution used in sample III 
