1998 - JAMB Chemistry Past Questions and Answers - page 3
21
2X(g) + Y(g) → Z(g): In the equation above, The rate of formation of Z is found to be independent of the concentration of Y and to quadruple when the concentration of X is doubled. The correct equation for the reaction is?
A
R = k (X)(Y)
B
R = K (X) ° (Y)
C
R = K (X) ° (Y) 2
D
R = K (X) 2(Y)°
correct option: d
Users' Answers & Comments22
A gas that turns a filter paper previously soaked in lead ethanoate solution black is?
A
hyrogen chloride
B
hydrogen sulphide
C
sulphur (IV) oxide
D
sulphur (VI) oxide
correct option: b
Users' Answers & Comments23
3CuO(s) + 2NH3(g) → 3Cu(s) + 3H2O(I) N2(g) (i).
2NH3(g) + 3Cl2(g) → 6HCl(g) + N2(g) (ii).
4NH3(g) + 3O2(g) → 6H2O(I) + 2N2(g) (iii).
The reactions represented by the equations above demonstrate the?
2NH3(g) + 3Cl2(g) → 6HCl(g) + N2(g) (ii).
4NH3(g) + 3O2(g) → 6H2O(I) + 2N2(g) (iii).
The reactions represented by the equations above demonstrate the?
A
basic properties of ammonia
B
acidic properties of ammonia
C
reducing properties of ammonia
D
oxidizing properties of ammonia
correct option: c
Users' Answers & Comments24
A solution containing chloride ions gives white precipitate with silver trioxonitrate(V) Solution. The precipitate will be insoluble in dilute?
A
HNO 3 but soluble in ammonia solution
B
HNO3 and ammonia solution
C
HCl but soluble in ammonia solution
D
HCl and in ammonia solution
correct option: a
Users' Answers & Comments25
The oxide that remains unchanged when heated in hydrogen is?
A
CuO
B
Fe2O3
C
PbO2
D
ZnO
correct option: b
Users' Answers & Comments26
Which of the following is observed when a solution of iron (III) chloride is mixed with a solution of sodium hydroxide?
A
A gas is evolved
B
A deep blue precipitate is formed
C
The resultant solution turns green turns
D
A brown precipitate is formed
correct option: d
iron(III) chloride is a yellow solution
sodium hydroxide is colourless
iron(III) hydroxide is a reddish brown precipitate
sodium chloride is colourless
So in the reaction, yellow solution when added to sodium hydroxide forms reddish brown precipitate that is insoluble in excess sodium hydroxide.
Users' Answers & Commentssodium hydroxide is colourless
iron(III) hydroxide is a reddish brown precipitate
sodium chloride is colourless
So in the reaction, yellow solution when added to sodium hydroxide forms reddish brown precipitate that is insoluble in excess sodium hydroxide.
27
The metal that will react with water only in the form of steam to librate hydrogen gas is?
A
calcium
B
aluminium
C
iron
D
zinc
correct option: c
Users' Answers & Comments28
A common characteristic shared by iron and aluminium is that both?
A
are extracted by reduction methods
B
form only basic oxides
C
show oxidation states of +2 and +3
D
form soluble hydroxides
correct option: a
Users' Answers & Comments29
Alloys are often used in preference to pure metals because?
A
metals are too hard
B
merals are ductile
C
metallic properties are improve in alloys
D
alloys are a mixture of metals
correct option: c
Users' Answers & Comments30
One mole of hydrocarbon contains 6g of hydrogen. If the molecular weight is 54, the hydrocarbon is an?
A
alkanone
B
alkane
C
alkene
D
alkyne
correct option: d
CxH6
∴ CxH6 = 54
12x + 6 = 54
12x = 54 - 6
12x = 48
x = (48)/(12)
x = 4
We have CxH6 butyne
A formular of alkyne
Users' Answers & Comments∴ CxH6 = 54
12x + 6 = 54
12x = 54 - 6
12x = 48
x = (48)/(12)
x = 4
We have CxH6 butyne
A formular of alkyne