Alkenes：練習題

What is observed when ethene is added to aqueous bromine?

Ethene is reacted with steam in the presence of an acid catalyst. What is the product of this reaction?

A long-chain alkane with the formula \(C_{12}H_{26}\) is cracked to produce one molecule of propene, one molecule of ethene, and one molecule of an unknown alkane \(X\).
What is the formula of alkane \(X\)?

But-2-ene is an unsaturated hydrocarbon. Which structural formula represents the product formed when but-2-ene reacts with hydrogen in the presence of a nickel catalyst?

State the observation when ethene gas is bubbled through a test-tube containing aqueous bromine.

State the two essential conditions required for the cracking of long-chain alkanes to produce alkenes.

Name the product formed when ethene reacts with steam in the presence of an acid catalyst and identify the specific type of reaction that occurs.

Ethene, \( \text{C}_2\text{H}_4 \), is an unsaturated hydrocarbon and a member of the alkene homologous series.

(a) Describe the process of cracking used to manufacture ethene from larger alkane molecules, including the necessary conditions.

(b) Alkenes react with aqueous bromine.

(i) State the color change observed when aqueous bromine is added to ethene.

(ii) Name the type of reaction that occurs.

(c) Ethene can be converted into ethanol by reacting it with steam. State the catalyst and the temperature required for this industrial process.