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Chemistry Past Questions

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47 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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47 questions

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Question 21

waec 2013

The element with electron configuration 1s\(^2\) 2s\(^2\) 2p\(^6\) 3s\(^2\) 3p\(^1\) belongs to

As-block period 3, group 1

Bp-block, period 3, group 2

Cs-block, period 3, group 3

Dp-block, period 3, group 3

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Question 22

waec 2013

Which of the following arrangements represents the correct order of electronic energy level?

A1s 2p 2s 3p 3s 3d 4s

B1s 2s 2p 3s 3p 3d 4s

C1s 2s 2p 3s 3p 4s 3d

D1s 2s 3s 2p 3p 4s 3d

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Question 23

waec 2013

Which of the following statements is correct?

AAtomic size decreases down the group

BAtomic size increases across the period

CAnions are smaller than the parent atom

DCations are smaller than the parent atom

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Question 24

waec 2013

An atom of an element X gains two electrons. The symbol of the ion formed is

AX ⁺

BX ²⁺

CX ^2-

DX ^-

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Question 25

waec 2013

The formula of the compound formed between a trivalent metal, M and a divalent non-metal, Y is

AM₂Y₃

BM₃Y₂

CMY

DM₃Y

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Question 26

waec 2013

The molecule which has a linear shape is

ACH₄

BNH₃

CH₂S

DCO₂

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Question 27

waec 2013

Which of the following instruments is used in detecting the presence of radiation?

ACathode ray tube

BGeiger-Muller counter

CMass spectrometer

DX-ray tube

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