Science MCQs

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

Total Questions
2100
Page 74 of 210
Question 731 Easy

What is the valency of the hydroxide ion (OH⁻)?

A
1
B
2
C
3
D
4
Question 732 Easy

The formula CaCl₂ shows that the valency of calcium is:

A
1
B
2
C
3
D
4
Question 733 Easy

Which subatomic particle is directly involved in chemical bonding?

A
Proton
B
Neutron
C
Electron
D
Nucleus
Question 734 Easy

The symbol 'aq' in a chemical formula stands for:

A
Solid
B
Liquid
C
Gas
D
Aqueous
Question 735 Hard

What is the formula for the compound formed between Potassium (K⁺) and Sulfate (SO₄²⁻)?

A
KSO₄
B
K₂SO₄
C
K(SO₄)₂
D
K₂SO₃
Question 736 Hard

Which of the following shows the correct electron dot structure for a molecule of nitrogen (N₂)?

A
N
B
N::N
C
N:N
D
N≡N
Question 737 Hard

What is the formula for Ammonium Sulfate?

A
NH₄SO₄
B
(NH₄)₂SO₄
C
NH₄(SO₄)₂
D
(NH₄)₃SO₄
Question 738 Hard

How many single covalent bonds are present in a molecule of water (H₂O)?

A
1
B
2
C
3
D
4
Question 739 Hard

Which of the following statements about ionic compounds is TRUE?

A
They are formed between two non-metals.
B
They are formed by sharing electrons.
C
They consist of molecules.
D
They are formed from cations and anions.
Question 740 Hard

What is the valency of phosphorus in phosphorus pentachloride (PCl₅)?

A
3
B
4
C
5
D
6
Showing 731-740 of 2100 questions

Quick Stats

Total Questions 10900
easy 5797
medium 2983
hard 2120

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Did You Know?

Practice Makes Perfect

Regular practice with MCQs can improve your test-taking speed and accuracy by up to 40%.

Active Recall

MCQs engage active recall, which is 50% more effective for long-term memory than passive reading.