Alcohol | MCQs

Explanation

At 170°C, ethanol undergoes acid-catalyzed dehydration to form ethene (C₂H₄).

Concentrated H₂SO₄ acts as a dehydrating agent, removing water from ethanol.

Explanation

Explanation

Ethanol-blended fuel is widely used in Brazil

In the 1970s Brazil started a large-scale program for the use of sugarcane-derived ethanol as a motor fuel

Explanation

Hydrogen peroxide (H₂O₂) is commonly used as a disinfectant to kill bacteria, viruses, and fungi on surfaces.

It works by releasing oxygen when it comes into contact with the surface, which helps to destroy pathogens.

Additional information:

 While other substances like vinegar and lemon juice have some antimicrobial properties,

hydrogen peroxide is more effective as a disinfectant.

Explanation

When an alcohol reacts with an alkyl magnesium halide (Grignard reagent), the product is an alkane.

The Grignard reagent acts as a strong base, removing the acidic hydrogen from the alcohol's hydroxyl group (-OH) and forming a new carbon-hydrogen (C-H) bond, thus creating an alkane.

The other product is a magnesium alkoxide salt. 

Explanation

Explanation

• CH3-OH is the molecular formula for methanol, which is an alcohol.

Key Points:

• CH3-CHO is the molecular formula for acetaldehyde, which is an aldehyde.
• CH3-CH2-O-CH3 is the molecular formula for diethyl ether, which is an ether.
• HCOOH is the molecular formula for formic acid, which is a carboxylic acid.

Explanation

When ethanol is in excess and the temperature is around 140°C, concentrated H₂SO₄ acts as a dehydrating agent and promotes the formation of diethyl ether:

2CH₃CH₂OH → CH₃CH₂–O–CH₂CH₃ + H₂O

So, the major product is ether (specifically diethyl ether) under these conditions.

Explanation

The appearance of cloudiness in the Lucas test for alcohol is due to the formation of alkyl chlorides. 

Explanation

Lithium aluminium hydride (LiAlH₄) is a strong reducing agent.

It reduces carboxylic acids to primary alcohols effectively.