Science MCQs

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

Total Questions
2100
Page 168 of 210
Question 1671 Easy

What is valency?

A
Number of protons
B
Number of neutrons
C
Combining capacity
D
Mass number
Question 1672 Easy

Sodium (Na) has a valency of?

A
1
B
2
C
3
D
4
Question 1673 Easy

Oxygen has a valency of?

A
1
B
2
C
3
D
4
Question 1674 Easy

What is an ion?

A
A neutral atom
B
A charged atom
C
A molecule
D
An isotope
Question 1675 Easy

A positively charged ion is called a?

A
Anion
B
Cation
C
Neutron
D
Electron
Question 1676 Easy

A negatively charged ion is called a?

A
Cation
B
Anion
C
Proton
D
Neutron
Question 1677 Easy

How is a sodium ion (Na⁺) formed?

A
Gains a proton
B
Loses an electron
C
Gains an electron
D
Loses a neutron
Question 1678 Easy

How is a chloride ion (Cl⁻) formed?

A
Loses an electron
B
Gains an electron
C
Loses a proton
D
Gains a neutron
Question 1679 Easy

What are isotopes?

A
Atoms of different elements
B
Atoms with same atomic number but different mass numbers
C
Atoms with same mass number but different atomic numbers
D
Charged atoms
Question 1680 Easy

Hydrogen has three isotopes: Protium Deuterium and?

A
Tritium
B
Oxygen
C
Carbon
D
Helium
Showing 1671-1680 of 2100 questions

Quick Stats

Total Questions 10900
easy 5797
medium 2983
hard 2120

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