Problem 156 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the following: List I 1\. absolute alcohol 2\. denatured alcohol 3\. \(80 \%\) proof alcoholic liquor 4\. rubbing alcohol List II (i) alcohol made undrinkable by the addition of toxic materials or poisons. (ii) alcoholic liquor containing \(40 \%\) ethanol by volume (iii) anhydrous alcohol (iv) isopropyl alcohol The correct matching is: \(\begin{array}{llll}1 & 2 & 3 & 4\end{array}\) (a) (i) (iii) (ii) (iv) (b) (iii) (i) (ii) (iv) (c) (i) (iii) (iv) (ii) (d) (iii) (i) (ii) (iv)

Step-by-Step Solution

Answer

The correct answer is (b).

Step 1: Understanding Absolute Alcohol

Absolute alcohol refers to anhydrous ethanol. This means it is ethanol that has no water content. Therefore, the match for absolute alcohol in List II is (iii) anhydrous alcohol.

Step 2: Understanding Denatured Alcohol

Denatured alcohol is ethanol that has been made unfit for human consumption by adding toxic substances or dyes. In List II, this corresponds to (i) alcohol made undrinkable by the addition of toxic materials or poisons.

Step 3: Understanding 80% Proof Alcoholic Liquor

Alcoholic proof is a measure of the strength of a spirit. In the United States, proof is twice the percentage of alcohol by volume. Therefore, an 80% proof alcoholic liquor contains 40% ethanol by volume, matching with (ii) alcoholic liquor containing 40% ethanol by volume.

Step 4: Understanding Rubbing Alcohol

Rubbing alcohol commonly refers to isopropyl alcohol, which is often used for disinfecting purposes. The match in List II is (iv) isopropyl alcohol.

Step 5: Determining the Correct Answer Choice

The correct matches are: 1-(iii), 2-(i), 3-(ii), and 4-(iv). Looking at the provided choices, (b) corresponds to these mappings: (iii), (i), (ii), and (iv).

Key Concepts

Absolute Alcohol

Absolute alcohol is a term used to describe ethanol that has been purified to remove any water content. This level of purity is also known as anhydrous alcohol, which simply means 'without water.'
When ethanol is created, it's usually mixed with a small amount of water. To achieve absolute alcohol, this water must be removed through processes such as distillation or the use of drying agents.

• Pure ethanol
• No water content
• Highly flammable

Absolute alcohol is often used in scientific research or industrial applications where the highest purity is needed. Because of its purity, it's unsafe for consumption.

Denatured Alcohol

Denatured alcohol is ethanol that has been mixed with additives to make it unsuitable for drinking. These additives can be toxic substances or other chemicals which don't alter its function but make it inedible.
This kind of alcohol is primarily used for industrial and household purposes.

• Additive-laden ethanol
• Used in cleaning products
• Not safe for consumption

The main reason for denaturing alcohol is to deter people from drinking it, in addition to avoiding the taxes applied to consumable alcohol. It's commonly employed as a solvent or cleaning agent in various industries.

Proof Alcoholic Liquor

Proof alcoholic liquor refers to a measurement of the alcohol content within a beverage. The term 'proof' varies between countries, but in the United States, the proof is calculated as double the percentage of alcohol by volume.
An 80% proof beverage would therefore contain 40% alcohol by volume.

• Measurement of alcohol strength
• U.S. proof = 2 x alcohol volume percentage
• Commonly on labels of spirits

This system helps consumers understand the potency of different alcoholic drinks, indicating how strong or weak a particular spirit might be.

Rubbing Alcohol

Rubbing alcohol typically refers to isopropyl alcohol, a type of alcohol used primarily for its antiseptic properties.
It is widely used for disinfecting, cleaning minor cuts, and as a skin sanitizer.

• Isopropyl alcohol
• Antiseptic & disinfectant
• Not for consumption

Rubbing alcohol comes in varying concentrations, often mixed with water. It is an essential item in first aid kits and is valued for its effectiveness in killing germs on contact.