5 Most SAQ’s of Carbon and its Compounds Chapter in Class 10th Physical Science (TS/AP)

4 Marks

SAQ-1 : Write the chemical formulas for the following compounds.
a) Propanoic acid b) Chlorobutane c) Hexanone d) Pentanal

Introduction

Chemical formulas represent the composition of compounds. They list elements present and indicate the number of atoms in a molecule. Different compounds have specific notation styles.

Chemical Formulas of Given Compounds:

1. Propanoic Acid:
   • Chemical Formula: C₃​H₆​O₂​ (Correction made)
   • Structure: Three-carbon chain with a carboxylic acid group (COOH).
2. Chlorobutane:
   • Chemical Formula: C₄​H₉​Cl
   • Structure: Four-carbon chain with a chlorine atom attached.
3. Hexanone:
   • Chemical Formula: C₆H₁₂O
   • Structure: Six-carbon chain with a ketone group (COCO).
4. Pentanal:
   • Chemical Formula: C₅H₁₀O
   • Structure: Five-carbon chain with an aldehyde group (CHO).

Summary

Understanding the chemical formulas and structures of compounds like propanoic acid, chlorobutane, hexanone, and pentanal is essential in chemistry. This knowledge helps in identifying their molecular composition, contributing to studies and reactions involving these compounds.

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SAQ-2 : Give the names of functional groups

i) –CHO ii) –C = 0.

Introduction

Functional groups are specific atoms or bonds within molecules that significantly affect the chemical properties of those molecules. These groups are crucial in determining how a molecule behaves in chemical reactions.

Functional Groups and Examples:

1. –CHO:
   • Name: Aldehyde
   • Example: Formaldehyde (HCHO)
2. –C=O:
   • Name: Ketone
   • Example: Propanone (CH₃(C=O)CH₃​)

Summary

In conclusion, the functional group –CHO is known as an aldehyde, and –C=O is a ketone. Identifying these functional groups in organic molecules is vital for understanding their chemical behavior and reactivity. This knowledge aids in the identification and analysis of various organic compounds.

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SAQ-3 : Draw the shape of methane molecule.

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SAQ-4 : Give an example for esterification reaction.

Introduction

Esterification is a chemical reaction where a carboxylic acid reacts with an alcohol, producing an ester and water. This reaction often requires an acid catalyst.

Esterification Reaction Example:

1. Reactants:
   • Carboxylic Acid: Ethanoic Acid (Acetic Acid, CH₃COOH)
   • Alcohol: Ethanol (C₂H₅OH)
   • Catalyst: Concentrated Sulfuric Acid (H₂SO₄)
2. Reaction: Ethanoic acid and ethanol react in the presence of concentrated sulfuric acid, forming ethyl acetate and water:
   $$\text{CH}_3\text{COOH} + \text{C}_2\text{H}_5\text{OH} \rightarrow \text{CH}_3\text{COOC}_2\text{H}_5 + \text{H}_2\text{O}$$
3. Products:
   • Ester: Ethyl Acetate (CH₃COOC₂H₅​)
   • Byproduct: Water (H₂O)
4. Name of the Reaction: This is an example of an esterification reaction.

Summary

The esterification reaction between ethanoic acid and ethanol, resulting in ethyl acetate and water, is an essential process in organic chemistry. Esterification reactions are significant due to their wide range of applications in various industries and pharmaceuticals.

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SAQ-5 : What are hydrophilic and hydrophobic parts in soaps?

Introduction

Soaps are molecules with dual nature, comprising parts that interact differently with water. Understanding the hydrophilic and hydrophobic parts of a soap molecule is crucial for grasping how soaps function to remove dirt and oil.

Hydrophilic and Hydrophobic Ends in Soaps:

1. Hydrophilic End:
   • Definition: The hydrophilic (water-attracting) end of a soap molecule is attracted to water.
   • Composition: It consists of a polar part, typically a carboxylate group (C – O).
   • Role: Facilitates the dissolving of soap in water, enabling interaction with oil and dirt.
2. Hydrophobic End:
   • Definition: The hydrophobic (water-repelling) end is repelled by water.
   • Composition: Comprises a non-polar hydrocarbon chain.
   • Role: Binds with oil and dirt, aiding their removal with water.

Soap’s Cleaning Action:

1. The hydrophilic end binds with water, while the hydrophobic end attaches to oils and fats.
2. This mechanism enables soaps to dissolve fats in water, resulting in effective cleaning of surfaces and skin.

Summary

In summary, soap molecules have a hydrophilic end that is attracted to water and a hydrophobic end that repels water. These components play a pivotal role in how soap cleans by binding to both water and oil particles, facilitating the removal of dirt and grease.