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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 2004

Which of the following electron transition results in the emission of energy?

A3p to 3s

B3p to 4p

C2s to 2p

D1s to 2s

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Question 22

waec 2004

The mass of an element is 27 and its atomic number is 13. What is the composition of the nucleus of its atom?

A13 electrons and 14 protons

B13 neutrons and 14 protons

C13 protons and 14 neutrons

D13 electrons and 14 neutrons