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Chemistry Past Questions

Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.

2,505 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Question 1 of 20 2,505 total questions
Question 1091
jamb 1984

If an excess of a liquid hydrocarbon is poured into a jar of chlorine, and the sealed jar is then exposed for several hours to bring sunlight, all the chlorine gas is consumed. The hydrocarbon is said to have undergone

Aa polymerization reaction
Ban isomerization reaction
Can addition reaction
Da substitution reaction
Ea reduction reaction
View Explanation & Discuss
Question 1092
jamb 1984
Alkanes
Aare all gases
Bhave the general formula CnH2n + 2O
Ccontain only carbon and hydrogen
Dare usually soluble in water
Eare usually active compounds
View Explanation & Discuss
Question 1093
jamb 1984
Sodium hydroxide (NaOH) pellets are
Adeliquescent
Bhygroscopic
Cefflorescent
Dhydrated
Efluorescent
View Explanation & Discuss
Question 1094
jamb 1984
Water is said to be 'hard' if it
Aeasily forms ice
Bhas to be warmed before sodium chloride dissolves in it
Cfroms an insoluble scum with soap
Dcontains nitrates
Econtains sodium ions
View Explanation & Discuss
Question 1095
jamb 1984
Nitrogen can best be obtained from a mixture over oxygen and nitrogen by passing the mixture over
Apotassium hydroxide
Bheated gold
Cheated magnesium
Dheated phosphorus
Ecalcium chloride
View Explanation & Discuss
Question 1096
jamb 1984

If the cost of electricity required to deposit 1 g of magnesium is N5.00, how much would it cost to deposit 10g of aluminium?

AN 10.00
BN27.00
CN44.44
DN66.67
EN33.33
View Explanation & Discuss
Question 1097
jamb 1984
Which of the following statements is NOT correct about all four of the acids: HBr, HNO3, H 2CO3 and H2SO4? They
Adissolve marble to liberate CO
Bhave a PH less than 7
CTurn blue litmus red
Dneutralize alkalis to form salt
Ereact with magnesium to liberate hydrogen
View Explanation & Discuss
Question 1098
jamb 1984
Which of the following statements is INCORRECT?
AFractional distillation of crude petroleum will give the folloing hydrocarbon fuels in order of increasing boiling point
BButane < petrol < kerosene of polythene.
CBoth but-1-ene and but-1-yne will decolorize bromine readily
Dbut-2-ene will react with chlorine to form 2,3-dichlorobutane
Ecalcuim carbide will react with water to form any alkyne
View Explanation & Discuss
Question 1099
jamb 1984
Alkaline hydrolysis of naturally occurring fats and oils yields
Afats and acids
Bsoaps and glycerol
Cmargarine and butter
Desters
Edetergents
View Explanation & Discuss
Question 1100
jamb 1984
When the kerosene fraction from petrol is heated at high temperature, a lower boiling liquid is obtained. This process is known as
Apolymerization
Brefining
Chydrogenation
Dcracking
View Explanation & Discuss
Question 1101
jamb 1984

An organic compound with a vapour density 56.5 has the following percentage composition:C =53.1% N = 12.4%, O = 28.3%, H = 6.2%. The molecular formula of the compound is
Relative atomic masses: N = 14, O = 16, C = 12, H = 1 )

AC3H6O2N
BC5H6O2N
C(C5H7O2N)1/2
DC5H7O2N
E(C5H7O2N)2
View Explanation & Discuss
Question 1102
jamb 1984
The hybridization of the carbon atom in ethyne is
Asp 4
Bsp 3
Csp2
Dsp
Es
View Explanation & Discuss
Question 1103
jamb 1984
In the Haber process for the manufacture of ammonia, finely divided iron is used as
Aan ionizing agent
Ba reducing agent
Ca catalyst
Da dehydrating agent
Ean oxidizing agent
View Explanation & Discuss
Question 1104
jamb 1984
3Cl2 + 2NH3 \(\to\) N2 + 6HCl. In the above reaction, ammonia acts as
Aa reducing agent
Ban oxidizing agent
Can acid
Da catalyst
Ea dry agent
View Explanation & Discuss
Question 1105
jamb 1984
An example of a neutral oxide is
AAL2O3
BNO2
CCO2
DCO
ESO2
View Explanation & Discuss
Question 1106
jamb 1984
From the reactions : ZnO + Na2O \(\to\) NaZnO and ZnO + CO2 \(\to\) ZnCO3 it may be concluded that zinc oxide is
Aneutral
Bbasic
Cacidic
Damphoteric
Ea mixture
View Explanation & Discuss
Question 1107
jamb 1984
Which of the following statements is NOT true of carbon monoxide?
ACO is poisonous
BCO is readily oxidized at room temperature by air to form CO2
CCO may be prepared by reducing CO2 mixed with coke heated to about 1000oC
DCO may be prepared by heating charcoal with a limited amount of O2
ECO is a good reducing agent
View Explanation & Discuss
Question 1108
jamb 1984
Sulphur
Aforms two alkaline oxides
Bis spontaneously flammable
Cburns with a blue flame
Dconducts electricity in the molten state
Eis usually stored in the form of sicks in water
View Explanation & Discuss
Question 1109
jamb 1984
An element that can exist in two or more different structural forms which possess the same chemical properties is said to exhibit.
Apolymerism
Bisotopy
Cisomorphism
Disomerism
Eallotrophy
View Explanation & Discuss
Question 1110
jamb 1984
Lime - water, which is used in the laboratory for the detection of carbon(iv)oxide is an aqueous solution of
ACa(OH)2
BCaCO3
CCaHCO3
DCaSO4
EN2CO3
View Explanation & Discuss
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