What is the number of electrons in the following ion?
Correct answer: A. 28
- A. 28
- B. 29
- C. 30
- D. 34
Explanation
No of electrons = no of protons = atomic number in a neutral atom. Since Ga-69 has atomic number 31 so its number of electrons is also 31 however by to question which is concerned with the number of electrons in Ga+3 ion, meaning this atom has lost 3 electrons so we subtract 3 from 31, we get 28. So the number of electrons in Ga+3 ion is 28. Hence option A is correct.
This question appeared on the UHS MDCAT 2017 paper, which you can sit online with every answer explained.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Electronic Configuration
Electronic configuration describes how electrons occupy shells, subshells and orbitals around an atom. Questions use the Aufbau principle, Pauli exclusion principle and Hund's rule to write configurations, identify valence electrons, form ions and explain periodic trends, including common exceptions such as chromium and copper.
Practise Atomic Structure
922 free Atomic Structure MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Electronic Configuration questions
Scandium has the atomic number 21, which one will be its electronic configuration?
With increase in number of unpaired electrons, paramagnetism:
More energy is needed to remove an electron from _.
Oxygen molecule has two unpaired electrons. It is therefore,
Na+ is isoelectronic with:
Which of the following pairs has the same electronic structure?