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Chemistry Past Questions

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2,505 questions

Question 1 of 20 2,505 total questions

Question 321

jamb 2017

The carbon atoms on ethane are

Asp² hybridized

Bsp³ hybridized

Csp⁴ hybridized

Dsp hybridized

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Question 322

jamb 2017

The densities of two gases, X and Y are 0.5gdm^-3 and 2.0gdm^-3 respectively. What is the rate of diffusion of X relative to Y?

A0.1

B0.5

C2.0

D4.0

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Question 323

jamb 2017

The reddish–brown rust on iron roofing sheets consists of

AFe³ + (H₂O)₆

BFeO.H₂O

CFe₂O₃.XH₂O

DFe₃O₄.2H2₂O

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Question 324

jamb 2017

The IUPAC nomenclature of the structure above is

A3-methybut-3-ene

B2-methylbut-1-ene

C2-ethylprop-1-ene

D2-methylbut-2-ene

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Question 325

jamb 2017

Calculate the mass of copper deposited when a current of 0.5 ampere was passed through a solution of copper(II) chloride for 45 minutes in an electrolytic cell. [Cu = 64, F = 96500Cmol^-1]

A0.300g

B0.250g

C0.2242g

D0.448g

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Question 326

jamb 2017

The diagram above. Y is

Afused CaO

BH₂O

CNaOH

DConcentrated H₂SO₄

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Question 327

jamb 2017

In the diagram above. X is

ASO₃

BSO₂

DH₂S

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Question 328

jamb 2017

Cu\(_2\)S(g) + O\(_2\)(g) → 2Cu + SO\(_2\)(g)
What is the change in the oxidation number of copper in the reaction?

A0 to + 2

B0 to + 1

C+ 1 to 0

D+ 2 to + 1

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Question 329

jamb 2017

The alkyl group is represented by the general formula

AC_nH₂n

BC_nH₂n − 2

CC_nH₂n + 1

DC_nH₂n + 2

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Question 330

jamb 2017

The enzyme used in the hydrolysis of starch to dextrin and maltose is?

Alipase

Bamylase

Cinvertase

Dzymase

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Question 331

jamb 2017

The reaction of halogens with alkanes in the presence of sunlight is an example of

Aoxidation reaction

Baddition reaction

Chydrogenation reaction

Dsubstitution reaction

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Question 332

jamb 2017

Calculate the amount in moles of silver deposited when 9650C of electricty is passed through a solution of silver salt [= 96500 Cmol^-1]

A0.05

B10.80

C10.00

D0.10

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Question 333

jamb 2017

Tin is unaffected by air at ordinary temperature due to its?

ALow melting point

BWeak electropositive character

CHigh boiling point

DWhite lustrous appearance

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Question 334

jamb 2017

The mass of silver deposited when a current of 10A is passed through a solution of silver salt for 4830s is – (Ag = 108 F = 96500(mol-1)

A54.0g

B27.0g

C13.5g

D108.0g

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Question 335

jamb 2017

The shape of ammonia molecules is

Atrigonal pyramidal

Boctahedral

Csquare planar

Dtetrahedral

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Question 336

jamb 2017

\(^{226}_{88}Ra\) → \(^x_{86}Rn\) + alpha particle

A226

B220

C227

D222

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Question 337

jamb 2017

When ΔH is negative, a reaction is said to be

Aendothermic

Bexothermic

Creversible

Dionic

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Question 338

jamb 2017

The ideal gas laws and equations are true for all gases at

Alow pressures and lower temperatures

Blow temperatures and high pressures

Chigh pressures and high temperatures

Dlow pressure and high temperatures

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Question 339

jamb 2017

The salt formed from a weak acid and a strong base hydrolyzes in water to form

AA saturated solution

Ban acidic solution

Ca buffer solution

Dan alkaline solution

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Question 340

jamb 2017

Incomplete oxidation of ethanol yields

ACH₃COOH

BCH₃COCH₃

CCH₃CH₂OCH₂CH₃

DCH₃CHO

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