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Chemistry Past Questions

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4,306 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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4,306 questions

Question 1 of 20 4,306 total questions

Question 1251

waec 2003

Which of the following statements about dative bonding is not correct?

Athere is sharing of electrons

Bone atom must possess a lone pair electrons

Ceach participating atom contributes one electron

Dit can be formed between molecules

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Question 1252

waec 2003

An element X with electronic configuration \(1S^22S^22P^63S^2\) combines with another element Y with the configuration \(1S^2S^22P^23S^23P^5\). What is the formula of the compound formed?

AX₂Y₅

BX₂Y₃

CXY₃

DXY₂

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Question 1253

waec 2003

Group O of elements are unreactive because

Atheir outmost shells contain equal number of electrons

Btheir highest occupied enegy level is full

Cthey are monatomic gases

Dthey are non-metals

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Question 1254

waec 2003

The electronic configuration of an element is 1\(s^2\) 2\(s^2\) 2\(p^6\) 3\(s^2\) 3\(p^3\). Where is the element located in the periodic table?

AGroup lll, period 3

BGroup lll, period 5

CGroup V, period 3

DGroup V, period 5

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Question 1255

jamb 2003

2HCI(ag) + CaCO\(_3\)(s) → CaCl\(_2\)(s) + CO\(_2\)(g) + H\(_2\)O(l). From the reaction above, which of the curves in the diagram represents the production of carbon (IV) oxide as dilute HCI is added?

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Question 1256

jamb 2003

The principal constituent of natural gas is

Amethane

Bethane

Cpropane

Dbutane

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Question 1257

jamb 2003

Which of the following is found in cotton

AStarch

BCellulose

CFat

DOil

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Question 1258

jamb 2003

The process by which atoms are rearranged into different molecular structure in the petroleum refining process is referred to as

Acatalytic cracking

Bhydrocracking

Cpolymerization

Dreforming

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Question 1259

jamb 2003

A compound contains 40.0% carbon 6.7% hydrogen and 53.3% oxygen. If the molar mass of the compound is 180, find the molecular formula.
[H = 1, C = 12, O = 16]

ACH₂O

BC₃H₆O₃

CC₆H₁₂O₆

DC₆H₁₂O₃

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Question 1260

jamb 2003

Ethanol reacts with excess acidified K\(_2\)Cr\(_2\)O\(_7\) to produce

Aethanedioic acid

Bethanal

Cethylethanoate

Dethanoic acid

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Question 1261

jamb 2003

The type of reaction that is peculiar to benzene is?

Aaddition

Bhydrolysis

Cpolymerization

Dsubstitution

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Question 1262

jamb 2003

The formula for ethyl butanoate is

AC₃H₇COOC₂H₅

BC₂H₅COOC₃H₇

CC₄H₉COOC₂H₅

DC₂H₅COOC₄H₉

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Question 1263

jamb 2003

The leachate of a certain plant ash is used in local soap making because it contains

Asodium chloride and potassium hydroxide

Bsodium hydroxide

Cpotassium hydroxide

Dsoluble carbonates and hydrogen carbonates

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Question 1264

jamb 2003

How many isomers does pentane have?

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Question 1265

jamb 2003

Ethene reacts with hydrogen bromide to give

ACH₂Br₂

BCH₃CH₂Br

CC₂H₂Br₂

DCHBr₂

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Question 1266

jamb 2003

The modern process of manufacturing steel for iron is by

Atreatment with acids

Boxidation

Cblast reduction

Dtreatment with alkanal

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Question 1267

jamb 2003

Chlorine gas turns a damp starch-iodide paper

Apink

Bcolourless

Cred

Ddark blue

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Question 1268

jamb 2003

The metal that liberates hydrogen from cold water in bubbles only is?

ANa

CCa

DAl

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Question 1269

jamb 2003

The salt that will form a precipitate soluble in excess ammonia solution is

ACa(NO₃)₂

BCu(NO_{3_)₂}

CMg(NO_{3_)₂}

DAl(NO_{3_)₃}

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Question 1270

jamb 2003

Which of the following statements is true of sulphur (IV) oxide?

AIt forms tetraoxosulphate (VI) acid with water

BIt is an odourless gas

CIt is an acid anhydride

DIt forms white precipitate with acidified barium chloride

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