2008 - JAMB Chemistry Past Questions and Answers - page 4
31
Which of the following compounds of trioxonitrate (V) will decomposes to give dinitrogen (i) oxide and water when heated?
A
NaNO3
B
Zn(NO3)2
C
Cu(NO3)2
D
NH4NO3
correct option: d
Users' Answers & Comments32
When a solution of ammonium trioxocarbonate (IV) is added to a solution of an unknown salt, a white precipitate which is soluble in dilute hydrochloric acid but insoluble in ethanoic acid is formed. This indicates the presence of
A
Ca2+
B
Na+
C
Zn2+
D
K+
correct option: a
Users' Answers & Comments33
Leads is used for making bullets and lead shots because of its
A
resistance to corrosion
B
low melting point
C
high density
D
flexibility
correct option: c
Users' Answers & Comments34
which of the following gives a precipitate when treated with NaOH solution?
A
AlCl3
B
NH4Cl
C
Na2CO3
D
CH3COONa
correct option: a
Users' Answers & Comments35
The most common ores of iron include
A
haematite, malachite and limonite
B
chalcolite, calamine and bornite
C
magnetite, haematite and bornite
D
magnetite, chalcolite and bornite
correct option: c
Users' Answers & Comments36
The type of isomerism shown by cis- and trans- isomers is
A
optical isomerism
B
positional isomerism
C
functional isomerism
D
geometrical isomerism
correct option: d
Users' Answers & Comments37
If the silver mirror test is positive, it indicates the presence of an
A
alkyne
B
alkanol
C
alkanone
D
alkanal
correct option: d
Users' Answers & Comments38
If glucose is heated with concentration tetraoxosulphate (VI) acid, it will be dehydrated to
A
carbon
B
carbon (IV) oxide
C
ethene
D
ethanol
correct option: a
Users' Answers & Comments39
A
2, 3 - dichloro - 4, 4, 5 - trimethyl pent - 2 - ene
B
4, 5 - dichloro - 2, 3 - dimethyl hex - 2 - ene
C
2, 3 - dichloro - 4, 4 - dimethyl hex - 2- ene
D
2, 3 dichloro - 2, 2 - dimethyl hex - 2 - ene
correct option: c
Users' Answers & Comments40
A hydrocarbon X with a molar mass of 26 consists of 92.3% carbon. What is its molecular formular
A
C2H2
B
C3H3
C
C4H4
D
C5H5
correct option: a
% of H2 = 100 - 92.3 = 7.7%
mole = 92.3/12 7.7/1
7.1/7.1 7.1/7.1
empirical formula = CH
(CH)n = 26
(12 + 1)n = 26
(13)n = 26
n = 26/13 = 2
molecular formula = C2H2
Users' Answers & Commentsmole = 92.3/12 7.7/1
7.1/7.1 7.1/7.1
empirical formula = CH
(CH)n = 26
(12 + 1)n = 26
(13)n = 26
n = 26/13 = 2
molecular formula = C2H2