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What is the organic product of the reaction of C2H 5OH with excess acidified K 2Cr 2O7(aq)?
ACH3COOH
BC2H5OC2H5
CHCOOCH 3
DC2H5CHO
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Question 512
waec2003
Which of the following substances could be responsible for the banana taste of a food flavour?
AMethylbenzene
BButanol
CEthanol
DPentylethanoate
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Question 513
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Wine containing 8% to 17% ethanol can be converted to gin containing about 40% ethanol by
Aevaporation
Bdistilation
Cfermentation
Doxidation
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Question 514
waec2003
A given fuel has an octane number of 100. This means that
Athe knocking tendency of the fuel is low
Bthe fuel is a mixture of several hydrocarbons
Ca large amount of alkanes is present in the fuel
Dthe fuel needs to be cracked before use
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Question 515
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Which of the following compounds has the same empirical formula as benzene?
AC2H2
BC2H4
CC4H6
DC6H12
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Question 516
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The equation for the reaction at the anode during the electrolysis of concentrated sodium chloride solution is
A2CI-(aq) → CI,sub>2(g) + 2e-
B40H-(aq) → 2H2O(I) + O2(g) + 4e -
CNa+(aq) + e- → Na(s)
D2H+(aq) + 2e- → H2(g)
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Question 517
waec2003
A given fuel has an octane number of 100. This means that
Athe knocking tendency of the fuel is low
Bthe fuel is a mixture of several hydrocarbons
Ca large amount of alkanes is present in the fuel
Dthe fuel needs to be cracked before use
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Question 518
waec2003
Determine the amount of electrons needed to deposit 6.4g of copper during the electrolysis of copper (ll) tetraoxosulphate (IV) solution [Cu = 64]
A0.10 mole
B0.20 mole
C1.0 mole
D2.0 mole
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Question 519
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Which of the following statements is/are correct about tin plating? l The electrolyte must be a soluble salt of tin ll. the objective to be plated is made the cathode lll. The anode is made of tin lV. The negative electrode dissolves
AL only
Bl and ll only
Cl,ll and lll only
Dl, ll and lV only
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Question 520
waec2003
Five metals represented by the letters V to Z are arranged in order of their reactivity as shown . V>W>X>Y>Z.
Which of the metals is most likely extracted by the electrolysis of its fused chloride?
AV
BW
CX
DZ
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Question 521
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Five metals represented by the letters V to Z are arranged in order of their reactivity as shown . V>W>X>Y>Z.
Which of the metals cannot displace Y from an aqueous solution of its salt?
AV
BW
CX
DZ
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Question 522
waec2003
Consider the electrochemical cell represented below Zn(s)/Zn2+(aq)//Cu2+(aq)/Cu(s). Which of the following equations describes the reaction occurring in the cell?
ACu(s) + Zn2+(aq) →Cu2+(aq) + Zn(s)
BCu(s) + Zn(s) →Cu2+(aq) + Zn2+(aq)
CZn(s) + Cu2+(aq) →Zn2+(aq) + Cu(s)
DZn2+(aq) +Cu2+(aq) → Zn(s) + Cu(s)
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Question 523
waec2003
A reducing agent is expected to
Adecolourize acidified KMnO4 solution
Bdecolourize acidified FeSO4 solution
Cliberate CI2 from a chloride
Dliberate CO2 from NaHCO3
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Question 524
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Which of the following statements about an exothermic reaction is correct?
Athe products have less heat content than reactants
Bthe system absorbs heat from the surrounding
Cthe activation energy is high
Dthe enthalpy change is positive
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Question 525
waec2003
Sea shells contain mainly CaCO 3. Calcium oxide can be prepared from sea shells by
Aadding dilute acid
Bheating at a high temperature
Creduction with CO
Dadding dilute NaOH(aq)
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Question 526
waec2003
Which of the following processes involves neutralization?
AHardening of oils
BSouring of milk
CCharring of sugar
DLiming of soil
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Question 527
waec2003
The pH of 0.50 mol dm-3 solutions of HCI, H2SO4 and CH3COOH were measured. which of the following statements about the values obtained is correct?
Athe pH value was equal to 5 in each case
Bthe pH values of the HCI and H2SO4 solutions were equal
Ctheir pH values added uo to 14
Dthe pH value of the CH3COOH was the highest.
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Question 528
waec2003
What term is used to describe an oxide whose aqueous solution turns blue litmus red?
AStrong electrolyte
BAcid anhydride
CAmphoteric oxide
DBasic oxide
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Question 529
waec2003
Substance Q reacts with cold water to form a solution which turns red litmus blue. Substance Q could be
Azinc
Bphosphorus
Clead
Dsodium
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Question 530
waec2003
Which of the following solutions will give a precipitate with dilute tetraoxosulphate (V) acid? l. Lead (ll) trioxonitrate (V) solution ll. Barium chloride solution lll. Sodium chloride solution
