Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
cyclohexane
cyclopentane
n- hexane
n - pentane
Correct answer is A
When a mixture of benzene vapour and hydrogen are passed over a nickel catalyst at 180ºc cyclohexane will be produced
Reduction of alkanones with LialH4 produces
primary alkanols
secondary alkanols
tertiary alkanols
polyhydric alkanols
Correct answer is B
Reduction of alkanones with \(LiAlH_4\) produces secondary alkanols.
Reduction of nitroalkanes, nitrites and amides is a route for the preparation of
amines
alkenes
polymers
detergents
Correct answer is A
Reduction of nitroalkanes, nitrites and amides is a route for the preparation of amines
A hydrocarbon X with a molar mass of 26 consists of 92.3% carbon. What is its molecular formular?
C2H2
C3H3
C4H4
C5H5
Correct answer is A
% of H2 = 100 - 92.3 = 7.7%
mole = Carbon [92.3 / 12] = 7.7
Hydrogen [7.7 / 1] = 7.7
divide with the lowest:
Carbon - 7.1 / 7.1 = 1
Hydrogen - 7.1 / 7.1 = 1
empirical formula = CH
(CH)n = 26
(12 + 1)n = 26
(13)n = 26
n = 26/13 = 2
molecular formula = C\(_2\)H\(_2\)
The IUPAC nomenclature for the structure above is
2, 3 - dichloro - 4, 4, 5 - trimethyl pent - 2 - ene
4, 5 - dichloro - 2, 3 - dimethyl hex - 2 - ene
2, 3 - dichloro - 4, 4 - dimethyl hex - 2- ene
2, 3 dichloro - 2, 2 - dimethyl hex - 2 - ene
Correct answer is C
The longest carbon chain in the compound is the hex-2-ene.
Counting all the attachments, the IUPAC nomenclature of the compound is 2,3 - dichloro-4,4- dimethyl hex-2-ene.