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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.

52 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

52 questions
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Question 1 of 12 52 total questions
Question 21
waec 2002

If the relative molecular mass of an element is not a whole number, it can be deduced that the element is

Anaturally radioactive
Babundant in nature
Ca transition metal
Dan isotopic mixture
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Question 22
waec 2002
Which of the following statements about soapless detergents is correct? They
Alather readily with hard water
Bincrease the surface tension of water
Ccause hydrolysis of salts in water
Dfrom a curdy precipitate with soft water
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Question 23
waec 2002
The following compounds are hydrocarbons except
Amethylpropanoate
B2-methylbutane
Cbenzene
Dcyclohexane
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Question 24
waec 2002

When alkynes are hydrogenated completely, they produce compounds with the general molecular formula

AC nH n
BC nH 2n+2
CCnH 2n
DCnH2n-2
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Question 25
waec 2002
Which of the following compounds can be represented by the molecular formula C2H6O?
APropanel
BEthanol
CMethanoic acid
DGlucose
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Question 26
waec 2002

Which of the following processes takes place during the production of margarine from vegetable oils?

AEsterification
BHydrolysis
CHydrogenation
DSaponification
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Question 27
waec 2002

When concentrated sodium chloride solution is electrolysed using inert electrodes the products are?

Aoxygen and hydrogen
Bhydrogen and oxygen
Csodium and oxygen
Dsoduim hydroxide, hydrogen and chlorine
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Question 28
waec 2002
If two metallic ions of the same concentration migrate to a graphite cathode, the one that would be preferentially discharged is the one that has the
Asmaller mass
Blower electrical charge
Cgreater stability in solution
Dstronger tendency to accept electrons
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Question 29
waec 2002
Which of the following ions require the largest quantity of electricity for discharge at an electrode?
A2.0 mole of Q 3+
B2.5 mole of R2+
C4.0 mole of Y-
D3.0 mole of T-
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Question 30
waec 2002
Consider the following equation; Cr2O7(aq)2- + 14H+(aq) + 6e- → 2Cr3+(aq) + 7H2O(I). The oxidation number of chromium changes from
A-2 to + 3
B- 2 to + 6
C+ 6 to + 3
D+ 7 to + 6
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Question 31
waec 2002
The atomic number of chlorine is 17. What is the number of electrons in a chloride ion?
A16
B17
C18
D19
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Question 32
waec 2002
If the relative molecular mass of an element is not a whole number, it can be deduced that the element is
Anaturally radioactive
Babundant in nature
Ca transition metal
Dan isotopic mixture
View Explanation & Discuss
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