An atom has a net charge of -1 it has 18 electron and 20 neutron its mass number is
Correct answer: A. 37
- A. 37
- B. 32
- C. 35
- D. 20
Explanation
Atom A has 18 electrons with net charge of -1 which means it gained one electron. Hence number of proton= number of electron - atomic charge = 18 - 1 = 17 The number of proton will be 17. Now Mass number=number of proton + number of neutron Mass number = 17+20= 37
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