🧪 1985

JAMB Chemistry 1985 past questions

44 questions from the 1985 JAMB UTME Chemistry paper. Free, with answers where available.

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Chemistry JAMB 1985 Q1 ✓ Answer: C
Given the molecular mss of iron is 56 and that of oxygen is 16, how many moles of Iron (111) oxide will be contained in 1 kg of the compound?
A
25.0 moles
B
12.5 moles
C
6.25 moles
D
3.125 moles
E
0.625 moles
Chemistry JAMB 1985 Q1 ✓ Answer: C
The movement of liquid molecules from the surface of the liquid gaseous phase above it is known as
A
Brownian movement
B
Condensation
C
Evaporation
D
Liquefaction
Chemistry JAMB 1985 Q2 ✓ Answer: B
Which of the following conducts electricity?
A
Sulphur
B
Graphite
C
Diamond
D
Red phosphorus
E
Yellow phosphorus.
Chemistry JAMB 1985 Q2 ✓ Answer: D
What mass of a divalent metal M (atomic mass= 40) would react with excess hydrochloric acid to liberate 22 cm3 of dry hydrogen gas measured as S.T.P?
A
8.0 g
B
4.0 g
C
0.8 g
D
0.4 g [ G. M. V = 22.4 dm3]
Chemistry JAMB 1985 Q3 ✓ Answer: D
An organic compound contains 72% carbon 12% hydrogen and 16% oxygen by mass. The empirical formula of the compound is
A
C6H22O3
B
C6H10O3
C
C12H12O
D
C6H12O
E
C3CH10 ( H= 1, C = 12, O= 16).
Chemistry JAMB 1985 Q4 ✓ Answer: E
0.499 of CuSO4.xH2O when heated to constant weight gave a residue of 0.346 g. The value of x is
A
0.5
B
2.0
C
3.0
D
4.0
E
5.0. (Cu = 63.5, S = 32.0 O = 16, H = 1).
Chemistry JAMB 1985 Q5 ✓ Answer: C
In an experiment which of the following observation would suggest that a solid sample is a mixture? The
A
solid can be ground to a fine powder
B
density of the solid 2.25 g dm-3
C
solid begins to melt until 648 K
D
solid absorbs moisture from the atmosphere and turns into a liquid
E
solid melts at 300 K.
Chemistry JAMB 1985 Q6 ✓ Answer: E
Hydrogen diffuses through a porous plug
A
at the same rate as oxygen
B
at a slower rare than oxygen
C
twice as fast as oxygen
D
three times as fast as oxygen
E
four times as fast as oxygen.
Chemistry JAMB 1985 Q9 ✓ Answer: D
At room temperature (300K)
A
Y is twice as soluble as X
B
X is twice as soluble as Y
C
X and Y soluble to the same extent
D
X is three times as soluble as Y
E
Y is three times as soluble as X
Chemistry JAMB 1985 Q10 ✓ Answer: C
If 80 g each of X and Y are taken up in 100g of water at 353 K we shall have.
A
only 10 g of X and Y undissolve
B
only 16 g of Y undissolve
C
10 g of X and 16 g of Y undissolved
D
all X and Y dissolved
E
all X and Y undissolved
Chemistry JAMB 1985 Q11 ✓ Answer: B
If the molar mass of X is 36 g, the number of moles of X dissolved at 343 is
A
0.2 moles
B
0.7 moles
C
1.5 moles
D
2.0 moles
E
3.0 moles
Chemistry JAMB 1985 Q12 ✓ Answer: C
Some properties of chemical substances are mentioned below (i) solar taste (ii)slippery to touch (iii)yields alkaline gas with ammonium salts (iv) has pH less than 7 (v) turns phenolphthalein pink. Which of the above are NOT typical properties of alkaline?
A
(i), (iv) and (v)
B
(iv) and (v) [PAGE 11]
C
(i) and (iv)
D
(ii) and (v)
E
(ii), (iii) and (v)
Chemistry JAMB 1985 Q14 ✓ Answer: B
Hydrogen is not liberated when trioxonirate (v) acid reacts with zinc because
A
Zinc is rendered passive by the acid
B
Hydrogen produced is oxidized to water
C
Oxides of nitrogen are produced
D
All nitrates are soluble in water
E
trioxonitrate v acid is a strong acid.
Chemistry JAMB 1985 Q15 ✓ Answer: C
The boiling points of water, ethanol, toluene and button-2-ol are 373.OK, 351.3K, 383.6 K and 372.5 K respectively. Which liquid has the highest vapour pressure at 323.0K?
A
water
B
Toluene
C
Ethanol
D
Butan-2-ol
E
None
Chemistry JAMB 1985 Q16 ✓ Answer: A
In what respect will two dry samples of nitrogen gas differ from each other if samples 1 is prepared by completely removing CO2 and O2 from air and sample 2 is prepared by passing purified nitrogen (i) oxide over heated copper? Sample 1 is
A
purer than sample 2
B
slightly denser than sample 2
C
in all respects the same as sample 2
D
colourless but sample 2 has a light brown.
E
slightly less reactive than sample 2
Chemistry JAMB 1985 Q17 ✓ Answer: D
Copper sulphate solution is electrolyzed using platinum electrodes. A current of 0.193 amperes is passed for 2hrs. How many grams of copper are deposited?
A
0.457 g
B
0.500 g
C
0.882 g
D
0.914 g
E
1.00 g (Cu = 63.5m F = 96500 coulombs)
Chemistry JAMB 1985 Q18 ✓ Answer: B
X + Y Z is an equilibrium reaction. The addition of a catalyst
A
increases the amount of W produced in a given time
B
increase the rate of change in concentrations of X, Y and Z
C
increases the rate of disappearance of X and Y
D
increases the rate of the forward reaction
E
decreases the amounts of X and Y left after the attainment of equilibrium.
Chemistry JAMB 1985 Q19 ✓ Answer: D
What is the formula of sodium gallate if gallium (Ga) shows an oxidation number of +3.
A
NaGaO3
B
Na2G(OH)2
C
NaGa(OH)3
D
NaGa (OH)4
E
NaGaO
Chemistry JAMB 1985 Q20 ✓ Answer: A
If the ONLY pollutants found in the atmosphere over a city are oxides of nitrogen suspended lead compounds, carbon monoxide and high level of methane, the probable source(s) of the pollution must be
A
automobile exhaust and biological decomposition
B
combustion of coal and automobile exhaust
C
biological decomposition only
D
combustion of coal, automobile exhaust and biological decomposition
E
combustion of coal and biological decomposition.
Chemistry JAMB 1985 Q23 ✓ Answer: D
2MnO4 - + 10Cl- + 16H + ’! 2Mn2+ + 5Cl2 + 8H2O. which of the substances serves as an oxidizing agent?
A
Mn2+
B
Cl-
C
H2O
D
MnO4
E
Cl2
Chemistry JAMB 1985 Q24 ✓ Answer: A
In the reaction H2O(g)’! H2(g) + ½O2(g) H=-2436000kJ2, which of the following has no effect on the equilibrium position?
A
Adding argon to the system
B
Lowering the temperature
C
Adding hydrogen to the system
D
Decreasing the pressure
E
Increasing the temperature.
Chemistry JAMB 1985 Q25 ✓ Answer: D
which of the following metals will displace iron from a solution of iron(11) tetraoxosulphate(1V)?
A
copper
B
mercury
C
silver
D
Zinc
E
Gold
Chemistry JAMB 1985 Q26 ✓ Answer: B
Complete hydrogenation of ethyne yields
A
benzene
B
methane
C
ethene
D
propane
E
Ethane
Chemistry JAMB 1985 Q27 ✓ Answer: B
Which of the following is used in the manufacture of bleaching powder?
A
sulphur dioxide
B
chlorine
C
hydrogen tetraoxosulphate
D
hydrogen sulphide
E
nitrogen dioxide
Chemistry JAMB 1985 Q29 ✓ Answer: E
When pollen grains are suspended in water and viewed through a microscope, they appear to be in a state of constant but erratic motion. This is due to
A
convection currents
B
small changes in pressure
C
small changes in temperature
D
a chemical reaction between the pollen grains and water
E
the bombardment of the pollen grains by molecules of water.
Chemistry JAMB 1985 Q30 ✓ Answer: A
The energy change (H) for the reaction CO(g) +½O2(g) CO2(g) is
A
-503.7 kJ
B
+503.7 kJ
C
–282.9 kJ
D
+282.9 kJ
E
+393.3 kJ ( Hi(CO) = -110.4 kJ mol-1( Hi(CO2) = -393 kJ mol-1
Chemistry JAMB 1985 Q32 ✓ Answer: A
The neutralization reaction between NaOH solution and nitrogen (1V) oxide (NO2) produces water and
A
NaNO2 and NaNO3
B
NaNO3 and HNO3
C
NaNO2
D
NaNO3
E
NaN2O3 CH3.
Chemistry JAMB 1985 Q33 ✓ Answer: D
The oxidation of CH- CH- C- O gives H H
A
2-butanone
B
2-butanal
C
butane
D
butanoic acid
E
3-butanal.
Chemistry JAMB 1985 Q34 ✓ Answer: B
Tetraoxosulphate (V1) ions are finally tested using
A
acidified silver nitrate
B
acidified barium chloride
C
lime – water
D
dilute hydrochloric acid
E
acidified lead nitrate
Chemistry JAMB 1985 Q35 ✓ Answer: D
The I.U.P.A.C name for the compound CH3 CH3- CH- CH –CH = CH - CH3 is
A
2-methl-3-patene
B
4-methy-2-pentane
C
2-methl-2-penten
D
4-methyl-3-pentene
E
2-methyl-3-pentane
Chemistry JAMB 1985 Q36 ✓ Answer: E
Mixing of aqueous solution of barium hydroxide and sodium tetraoxocarbonate(1V) yields a white precipitate of
A
barium oxide
B
sodium tetraoxocarbonate(1V)
C
sodium, oxide
D
sodium hydroxide
E
barium tetraoxocarbonate.
Chemistry JAMB 1985 Q37 ✓ Answer: C
An organic compound decolorized acidified KMnC4 solution but failed to react with ammoniacal silver nitrate solution. The organic compound is likely to be.
A
a carbonxyllic acicd
B
an alkane
C
an alkene
D
an alkyne
E
an alkanone
Chemistry JAMB 1985 Q38 ✓ Answer: C
Solid sodium hydroxide on exposure to air absorbs a gas and ultimately gives another alkaline substance with the molecular formula.
A
NaOH.H2O
B
NaOH.N2
C
Na2CO3
D
NaHCO3
E
NaNO3
Chemistry JAMB 1985 Q39 ✓ Answer: D
Which of the following is the functional group of carboxylic acids?
A
-OH
B
>C = O
C
>C-OH O
D
-C OH
E
-C = N [PAGE 13]
Chemistry JAMB 1985 Q40 ✓ Answer: E
Which of the following substances is the most abundant in the universe?
A
Carbon
B
Air
C
Water
D
Oxygen
E
Hydrogen Question 41 and 42 are based on the following. A colourless organic compound X was burnt in exces air to give two colourless and odourless grass, Y and Z , as products. X does not decolorize bomine vapour; Y turns lime milky while Z gives a blue colour with copper (11) tetraoxosulphate (V1).
Chemistry JAMB 1985 Q41 ✓ Answer: B
Compound X is
A
an alkene
B
an alkane
C
an alkyne
D
tetra chloromethane
E
Dichloromethane
Chemistry JAMB 1985 Q42 ✓ Answer: D
Y and Z are respectively.
A
CO2 and NH3
B
CO and NH3
C
SO2 and H2O
D
CO2 and H2O
E
SO2 and NH3
Chemistry JAMB 1985 Q43 ✓ Answer: C
Which of the following compounds is NOT the correct product formed when the parent metal is heated in air?
A
Calcium oxide (CaO)
B
Sodium oxide (Na2O)
C
Copper (11) oxide (CuO)
D
Tri-iron tetroxide (Fe3O4)
E
Aluminium oxide (Al2O3)
Chemistry JAMB 1985 Q45 ✓ Answer: E
When marble is heated to 1473 K, another whiter solid is obtained which reacts vigorously with water to give an alkaline solution. The solution contains
A
NaOH
B
KOH
C
Mg(OH)2
D
Zn(OH)2
E
Ca(OH)2
Chemistry JAMB 1985 Q46 ✓ Answer: C
Addition of dilute hydrochloric acid to an aqueous solution of a crystalline salt yielded a yellow precipitate and a gas which turned dichromate paper green. The crystalline salt was probably
A
Na2SO4
B
Na2S
C
NaS2O3.5H2O
D
NaCO3
E
NaHCO3
Chemistry JAMB 1985 Q47 ✓ Answer: A
The process involved in the conversion of an oil into margarine is known as
A
hydrogenation
B
condensation
C
hydrolysis
D
dehydration
E
cracking
Chemistry JAMB 1985 Q48 ✓ Answer: D
An aqueous solution of an inorganic salt gave white precipate (i) soluble in excess aqueous NaOH (ii) insoluble in excess aqueous NH3 (III) with dilute HCI. The caution present in the inorganic salt is
A
NH34 +
B
Ca++
C
N++
D
Al+++
E
Pb++
Chemistry JAMB 1985 Q49 ✓ Answer: D
Which of the following roles does sodium chloride play in soap preparation? It
A
reacts with glycerol
B
purifies the soap
C
accelerates the decomposition of the fat and oil
D
separates the soap form the glycerol
E
converts the fat acid to its sodium salt.
Chemistry JAMB 1985 Q50 ✓ Answer: C
The function of sulphur during the vulcanization of rubber is to .
A
act as catalyst for the polymerization of rubber molecules
B
convert rubber from thermosetting tio thermo plastic polymer
C
from chains which bind rubber molecules together
D
break down rubber polymer molecule
E
shorten the chain length of rubber polymer. Chemistry 1986