Gaokao Exam Chemistry: Organic Chemistry Fundamentals 3

Question 1

What is the structural difference between 1-butene and 2-butene?

Accepted Answer

The position of the double bond in the carbon chain

Answer

Both are C₄H₈ isomers with one double bond; they differ only in the position of the C=C double bond (between C1-C2 vs C2-C3).

Question 2

Which of the following compounds can be detected using the silver mirror reaction (Tollens' test)?

Accepted Answer

Glucose

Answer

Glucose contains an aldehyde group (-CHO) and acts as a reducing sugar, giving a positive silver mirror reaction. Sucrose is a non-reducing sugar.

Question 3

In the saponification reaction, which reagents are used to convert a fat into soap?

Accepted Answer

NaOH solution (heated)

Answer

Saponification is the alkaline hydrolysis of triglycerides (fats) using NaOH solution under heating to produce glycerol and sodium salts of fatty acids (soap).

Question 4

How many structural isomers does butane (C₄H₁₀) have?

Accepted Answer

2

Answer

Butane has 2 isomers: n-butane (straight chain: CH₃CH₂CH₂CH₃) and isobutane/2-methylpropane (branched: (CH₃)₃CH).

Question 5

Polyethylene is produced by the polymerization of ethylene (ethene). What type of reaction is this?

Accepted Answer

Addition polymerization

Answer

Ethylene (CH₂=CH₂) undergoes addition polymerization, where the C=C double bonds open and link to form the polymer chain -[CH₂-CH₂]ₙ- without releasing any small molecules.

Gaokao Exam Practice Test

Gaokao Exam Practice Test

Gaokao Exam Chemistry: Organic Chemistry Fundamentals 3