Which hydrocarbon has the molecular formula C₃H₈? MCQ with Answer and Explanation

Which hydrocarbon has the molecular formula C₃H₈?
A. Methane
B. Butane
C. Propane
D. Ethane
Answer: Option C
Solution (By JKExamLibrary)
Propane is an alkane with three carbon atoms: CH₃CH₂CH₃, formula C₃H₈. Methane: CH₄, Ethane: C₂H₆, Butane: C₄H₁₀. Propane is a component of LPG. Alkanes follow CnH₂n+2. For n=3, H=8. Propane is a gas at room temperature, liquefied under pressure. It is used as fuel for heating and cooking.

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More chemistry Questions

Question #1
Which of the following is used for softening hard water?
A. Baking soda
B. Bleaching powder
C. Plaster of Paris
D. Washing soda

Correct Answer: Option D


Explanation:
Washing soda (sodium carbonate, Na₂CO₃) is used to remove permanent hardness of water. It reacts with soluble calcium and magnesium chlorides/sulfates to form insoluble carbonates, which can be filtered out. Baking soda, bleaching powder, and plaster of Paris do not have this water-softening capability.

This question belongs to: Science chemistry
Question #2
PVC stands for:
A. Polyvinyl chlorate
B. Polyvinyl carbon
C. Polyvinyl carbide
D. Polyvinyl chloride

Correct Answer: Option D


Explanation:
PVC (polyvinyl chloride) is a polymer of vinyl chloride (CH₂=CHCl). It is used in pipes, electrical insulation, and flooring. It can be rigid (uPVC) or flexible with plasticizers. It is a thermoplastic. Chlorate/carbon/carbide are not correct expansions.

This question belongs to: Science chemistry
Question #3
Which of the following metals reacts with cold water?
A. Silver
B. Iron
C. Sodium
D. Copper

Correct Answer: Option C


Explanation:
The reactivity of metals with water depends on their position in the reactivity series. Sodium and potassium are highly reactive alkali metals that react vigorously and exothermically with cold water to form hydroxides and hydrogen gas. Iron reacts only with steam, while copper and silver do not react with water.

This question belongs to: Science chemistry