Science MCQs

Practice multiple choice questions with instant feedback. Select an option to see if you're correct.

Total Questions
2100
Page 73 of 210
Question 721 Easy

What is the maximum number of electrons the first shell (K) can hold?

A
2
B
8
C
18
D
32
Question 722 Easy

What is the maximum number of electrons the second shell (L) can hold?

A
2
B
8
C
18
D
32
Question 723 Easy

An atom with a stable electron configuration is most similar to a:

A
Metal
B
Non-metal
C
Noble gas
D
Metalloid
Question 724 Easy

What is the charge of a particle that has gained two electrons?

A
1
B
2
C
-1
D
-2
Question 725 Easy

The valency of an element is determined by the number of electrons in its:

A
Innermost shell
B
Outermost shell
C
Nucleus
D
Neutrons
Question 726 Easy

What is the valency of Helium?

A
1
B
2
C
0
D
4
Question 727 Easy

The chemical formula for common salt is:

A
NaO
B
NaCl
C
ClNa
D
Na₂Cl
Question 728 Easy

Which of the following is a monoatomic molecule?

A
Oxygen (O₂)
B
Helium (He)
C
Water (H₂O)
D
Ammonia (NH₃)
Question 729 Easy

Which of the following is a diatomic molecule?

A
Carbon (C)
B
Sulfur (S)
C
Nitrogen (N₂)
D
Iron (Fe)
Question 730 Easy

A group of atoms that behaves as a single unit and carries a charge is called a:

A
Molecule
B
Radical
C
Element
D
Compound
Showing 721-730 of 2100 questions

Quick Stats

Total Questions 10900
easy 5797
medium 2983
hard 2120

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Did You Know?

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