Chemistry

Periodic Classification and Elements

1,092 Questions

Periodic classification organizes chemical elements based on atomic structure, periodic laws, and elemental properties. It covers historical classification systems, electron configurations, and periodic trends. Test takers preparing for chemistry sections will find these questions crucial for mastering fundamental element properties and atomic interactions.

Periodic table structureAtomic orbitalsElement identificationPeriodic laws

Periodic Classification and Elements Questions

Multiple choice

Which among the following correctly defines the term atomicity?

  1. Number of atoms present in a molecule of an element.

  2. Number of protons present in an atom of molecule.

  3. Number of atoms present in a compound.

  4. Number of electrons present in an atom of an element.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The number of atoms present in a molecule of an element is called atomicity.

Multiple choice

Match the following elements with their valencies and choose the correct options given below

1.Bromine i. Tetravalent
2. Sulphur ii. Trivalent
3.Nitrogen iii. Monovalent
4. Carbon iv. Divalent

  1. 1-(i), 2-(ii), 3- (iii), 4- (iv)

  2. 1-(ii), 2- (i), 3- (iv), 4-(iii)

  3. 1- (iii), 2-(iv), 3-(ii), 4-(i)

  4. 1-(iv), 2-(iii), 3-(ii),4-(i)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
I. Bromine i. Monovalent
II. Sulphur ii. Divalent
III. Nitrogen iii. Trivalent
IV. Carbon iv. Tetravalent
Multiple choice

The symbol of an element represents

  1. one atom of the element

  2. one molecule of the element

  3. all the atoms of the element

  4. all the molecules of the element
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The symbol of an element represents one atom of the element.

Multiple choice

Electrons in the outer orbit are

  1. nuclei

  2. waves

  3. valence

  4. holes

  5. shells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Valence, also known as valency or valence number, is the number of valence bonds a given atom has formed or can form, with one or more atoms. For most elements the number of bonds can vary. Option 3 is correct.