Matching Chemical Names to Formulas

This question requires matching common chemical names to their correct chemical formulas. Let's break down each item to find the correct pairings.

Detailed Explanation of Each Chemical Match

• Item A: Chloroform

  Chloroform is a well-known organic compound, historically used as an anesthetic and currently used as a solvent. Its chemical formula is $CHCl_{\text{3}}$. This matches option 3.

• Item B: Phosgene

  Phosgene is an inorganic compound with the formula $COCl_{\text{2}}$. It is a highly toxic gas, famously used as a chemical weapon. This matches option 4.

• Item C: Tear gas

  Tear gas often refers to chemical compounds that cause irritation to the eyes, nose, and respiratory system. Chloropicrin, with the formula $CCl_{\text{3}} NO_{\text{2}}$, is one such compound used as a tear gas agent and formerly as an agricultural fumigant. This matches option 1.

• Item D: Mustard gas

  Mustard gas, specifically sulfur mustard, is a chemical warfare agent known for causing severe blisters. Its structure can be represented as $ClC_{\text{2}}H_{\text{4}}-S-C_{\text{2}}H_{\text{4}}Cl$. This matches option 2.

Determining the Correct Option

Based on the individual matches:

• Chloroform (A) matches with 3. $CHCl_{\text{3}}$
• Phosgene (B) matches with 4. $COCl_{\text{2}}$
• Tear gas (C) matches with 1. $CCl_{\text{3}} NO_{\text{2}}$
• Mustard gas (D) matches with 2. $ClC_{\text{2}}H_{\text{4}}-S-C_{\text{2}}H_{\text{4}}Cl$

The correct sequence for A, B, C, D is therefore 3, 4, 1, 2. This corresponds to option 3.