Chemistry · Physics

Atomic Structure and Mass

308 Questions

Atomic structure and mass focus on the composition of atoms, including protons, neutrons, electrons, and isotopes. This topic is essential for the chemistry sections in engineering and civil services competitive exams. Review these questions to practice calculating atomic mass, neutron count, and isotopic distributions.

Atomic mass unit calculationsNeutron and proton countsIsotopic distribution averagesLaw of triadsRest energy of atoms

Atomic Structure and Mass Questions

Multiple choice

Which among the following statements is/are false about ground state term?

  1. For ground state term, the value of spin multiplicity is the highest.
  2. If more than two states have the same spin multiplicity, then the term having the lowest value of L will be ground state term.
  3. For half filled or less than half filled orbital, the ground state term is that which has the highest value of J.

  1. Only 1

  2. Only 2

  3. Only 3

  4. 2 and 3

  5. 1 and 2
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This option is correct. If there are several terms with the same multiplicity, then the term having the largest value of L will be ground state term. For half filled or less than half filled orbital, the ground state term is that which has the lowest value of J. This option is wrong because statement 1 is correct.

Multiple choice

Which of the following is true about isobars?

  1. They occur at the same place in the periodic table.

  2. They have the same atomic mass.

  3. They have the same number of electrons.

  4. They are atoms of the same element.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 They have the same atomic mass.