Question
Which statements about ethanol are correct?
1 Ethanol is used as a solvent.
2 Ethanol can be made directly from ethane.
3 Ethanol is a covalent compound.
A. 1 only B. 1 and 2 C. 1 and 3 D. 2 and 3
▶️Answer/Explanation
Ans:
C
Ethanol cannot be made directly from ethane. Ethanol is typically produced through fermentation of sugars by yeast or other microorganisms, or by other chemical processes such as the fermentation of plant materials like corn, sugarcane, or cellulosic feedstocks.
Question
Which statements about ethanol are correct?
1 Ethanol is made by reacting steam with ethene at $300^{\circ} \mathrm{C}$.
2 Ethanol is made by fermentation at $55^{\circ} \mathrm{C}$.
3 Ethanol burns to produce carbon dioxide and water.
4 Ethanol contains a carbon-carbon double bond.
A 1 and 2
B 1 and 3
C 2 and 3
D 3 and 4
▶️Answer/Explanation
Ans:B
Ethanol can be synthesized through the reaction of steam (water vapor) with ethene (ethylene) in the presence of a catalyst, typically phosphoric acid, at around 300 degrees Celsius (°C). This process is known as the “ethene hydration” or “ethanol hydration” reaction.
When ethanol (C2H5OH) undergoes combustion, it reacts with oxygen to produce carbon dioxide and water as the primary products, along with heat and light.
Question
Which compound has a chemical name ending in –ol ?
A $\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}$
B $\mathrm{C}_2 \mathrm{H}_6$
c $\mathrm{CH}_3 \mathrm{COOH}$
D $\mathrm{C}_2 \mathrm{H}_4$
▶️Answer/Explanation
Ans:A
Alcohols have -OH group, and have chemical name ending in -ol. $\mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}$ is ethanol.
Question
The flow chart shows the preparation of ethanol and some important chemistry of ethanol.
$
\text { substance } X \stackrel{\text { fermentation }}{\longrightarrow} \text { ethanol } \stackrel{\text { process } Y}{\longrightarrow} \text { carbon dioxide + substance } Z
$
What are $\mathrm{X}, \mathrm{Y}$ and $\mathrm{Z}$ ?
▶️Answer/Explanation
Ans:B
Glucose can undergo fermentation to produce ethanol and carbon dioxide in the presence of yeast or other microorganisms. This process is commonly used to produce ethanol for various purposes, including the production of alcoholic beverages and biofuels.
When ethanol (C2H5OH) undergoes combustion, it reacts with oxygen to produce carbon dioxide and water (steam) as the primary products, along with heat and light.
Question
What is the total number of single covalent bonds in a molecule of ethanol?
A 5 B 6 C 7 D 8
▶️Answer/Explanation
Ans: D
Ethanol has 8 single covalent bonds.