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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.

42 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10

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Past Questions

42 questions

Question 1 of 2 42 total questions

Question 21

waec 1999

What is the electronic configuration of an element represented as 19₉X?

A1s ²2s² 2p ⁵

B1s²2s²3s²3p³

C1s² 2s² 2p ³3s²

D1s ²2s²2p ⁶3s²3p₆4s ₁

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Question 22

waec 1999

Which of the following atoms contains the highest number of electrons in the outermost shell?

A₈O

B₁₀Ne

C₁₅P

D₁₉K