Class 10 Chemistry Chapter 8
Study of Compounds : Hydrogen Chloride
Important Questions

Here, you'll discover significant inquiries pertaining to Chapter 8: Study of Compounds : Hydrogen Chloride for ICSE Class 10 Chemistry. These inquiries are carefully designed to aid students in preparing for the ICSE Class 10 Chemistry Examination in 2023–24. Engaging with different question formats allows students to address uncertainties, improve their exam preparedness, boost their self-assurance, and polish their ability to solve problems.

Introduction

In Chapter 8 of ICSE Class 10 Chemistry, which delves into the Study of compounds: Hydrogen Chloride, you will explore various aspects including:

• The preparation of hydrogen chloride from sodium chloride, with a detailed examination of laboratory procedures encompassing reactants, product formation, reaction conditions, equations, apparatus setup, procedure steps, observations, precautions, gas collection, and identification.
• Conducting a simple experiment to demonstrate the density of hydrogen chloride gas, which is found to be heavier than air.
• Investigating the solubility of hydrogen chloride through the fountain experiment, which involves apparatus arrangement, procedure description, observations, and inferences drawn from the experiment.
• Understanding the method for preparing hydrochloric acid by dissolving the gas in water, with a focus on the unique arrangement and the mechanism that prevents backflow.
• Exploring the reactions of hydrogen chloride with ammonia and the acidic properties of its solution, including interactions with metals, metal oxides, metal hydroxides, and metal carbonates, as well as the decomposition of carbonates, hydrogen carbonates, sulphides, and sulphites.
• Delving into precipitation reactions involving silver nitrate and lead nitrate solutions.
  

This chapter offers a comprehensive exploration of hydrogen chloride and its various chemical properties, reactions, and practical applications.

What is Study of Compounds : Hydrogen Chloride ?

Chapter 8 of ICSE Class 10 Chemistry,"Study of Compounds: Hydrogen Chloride," is a fundamental part of the curriculum that delves into the chemistry of hydrogen chloride (HCl) and its various properties, reactions, and practical applications. In this chapter, students are introduced to the following key concepts:

• Preparation of Hydrogen Chloride: Students learn how to prepare hydrogen chloride gas from common substances like sodium chloride (table salt). The laboratory methods are detailed, covering the reactants involved, the conditions required, chemical equations, apparatus setup, step-by-step procedures, observations, precautions, and methods for collecting and identifying the gas.
• Density Experiment: An experiment is conducted to demonstrate that hydrogen chloride gas is denser than air, leading to valuable insights into its physical properties.
• Solubility of Hydrogen Chloride: The chapter explores the solubility of HCl through a fascinating experiment known as the "fountain experiment." This experiment not only reveals the solubility of HCl but also reinforces important scientific principles related to gas behaviour.
• Preparation of Hydrochloric Acid: Students learn how hydrochloric acid (HCl) is prepared by dissolving hydrogen chloride gas in water. Special arrangements and mechanisms to prevent backflow are discussed.
• Chemical Reactions: The chapter delves into the chemical properties of hydrogen chloride, including its reactions with ammonia and its acidic properties when dissolved in water. These reactions are explored in the context of interactions with metals, metal oxides, metal hydroxides, and metal carbonates, as well as the decomposition of various compounds like carbonates, hydrogen carbonates, sulphides, and sulphites.
• Precipitation Reactions: The chapter concludes with discussions on precipitation reactions involving hydrogen chloride and solutions of silver nitrate and lead nitrate. These reactions are explored for their role in identifying specific ions in a solution.

In essence, "Study of Compounds: Hydrogen Chloride" provides students with a thorough understanding of the chemical behaviour of hydrogen chloride and its practical significance in various chemical processes. This knowledge equips students with a strong foundation in chemistry and prepares them for more advanced studies in the subject.

Class 10 Chemistry Chapter 8 Study of Compounds : Hydrogen Chloride Important Questions and Answers

Q1. The acid produced by the reaction of phosphorus pentoxide with HCl gas is:

Options

(a) H₃PO_3
‍(b) H₃PO_2
‍(c) H₃PO_4
‍(d) HPO₃

Ans. (d)

Explanation:
The reaction of phosphorus pentoxide with hydrogen chloride gives POCl₃ and HPO₃ acid. The reaction is shown as
\(P_2O_5+HCl\rightarrow POCl_3+HPO_3\)
POCl₃ is not acidic, and hence the acidic product is HPO₃.

Q2. An aqueous solution of HCl gas is named as:

Options

(a) Aqua fortis
(b) Aqua regia
(c) Oil of vitriol
(d) Muriatic acid

Ans. (d)
Explanation:
An aqueous solution of HCl gas is hydrochloric acid. It was first named by Lavoisier as muriatic acid. Later on, Davy, in 1810, named it as hydrochloric acid.

Q3. Mixture of sodium chloride and concentrated sulphuric acid does not heated above the temperature of 170°C while preparing hydrogen chloride. Why?

Explanation:
The mixture of sodium chloride and concentrated sulphuric acid is not heated above 170°C in preparing hydrogen chloride gas because at a higher temperature sodium sulphate is formed which is a hard
substance and difficult to remove from the reaction flask.
2NaCl+H₂SO₄→Na₂SO₄+2HCl

Q4. When the stopper of a bottle full of hydrogen chloride gas is opened there are fumes in the air?

Explanation:
When the stopper of a bottle full of hydrogen chloride gas is opened there are fumes in the air because hydrogen chloride gas has an affinity for water, hence, when the stopper is opened it immediately reacts with water vapour present in the atmosphere which leads to the formation of fumes.

Q5. Silver nitrate crystals are dissolved in distilled water and not in tap water in order to prepare a solution of silver nitrate as a laboratory reagent. Why?

Explanation:
Tap water always contains some amount of dissolved sodium chloride. Thus, when the solution of silver nitrate is prepared in tap water, it reacts to form curdy white precipitate of silver chloride.
AgNO₃+NaCl→AgCl+NaNO₃
To prevent the above chemical reaction, the solution of silver nitrate is prepared in distilled water.

ICSE Class 10 Chemistry Chapter wise Important Questions

Conclusion

Chapter 8 of ICSE Class 10 Chemistry, "Study of Compounds: Hydrogen Chloride," offers a valuable exploration of the properties, reactions, and practical applications of hydrogen chloride (HCl). This chapter equips students with essential knowledge about the preparation of HCl, its density, solubility, and its role in the formation of hydrochloric acid. Furthermore, it delves into the intriguing chemical reactions of HCl with other substances, emphasising its acidic properties and its use in precipitation reactions.To strengthen your grasp of the concepts covered in this chapter and excel in your chemistry studies, consider additional practice resources. Oswal.io provides an extensive collection of questions and study materials that are designed to enhance your learning experience.

Frequently Asked Questions

Q1 : What are the applications of Hydrochloric Acid?

Ans: Here are some of the utilizations of Hydrochloric acid:

• Employed for the purification of table salt.Utilized as neutralizers and for pH control.
• Acts as a cleaning agent for pool maintenance.
• Effective in eliminating metal stains and rust from iron surfaces.
• Plays a role in the production of both organic and inorganic compounds.

Q2: Explain why Hydrogen chloride gas cannot be dried over quicklime?

Ans:  Hydrogen chloride gas (HCl) undergoes a chemical reaction with quicklime. The equation is 2HCl + CaO → CaCl₂ + H₂O .

Q3 : What is the common property being shown by these metal oxides- Manganese dioxide, red lead and Lead(IV) oxide reacts with conc. HCl acid liberates Cl₂.

Ans: Manganese dioxide (MnO₂), red lead and Lead (IV) oxide (PbO₂) react with conc. HCl acid to liberate Cl₂. All these metal oxides show that hydrochloric acid is oxidised to chlorine by oxidising agents.

Q4 : What happens when Lead nitrate solution is mixed with dilute hydrochloric acid and heated.

Ans:  When Lead nitrate Pb(NO₃)₂ solution is mixed with dilute hydrochloric acid (2HCl) and heated to give a white precipitate of lead (I) chloride (PbCl₂). The balanced equation is:
Pb(NO₃)₂ + 2HCl → (PbCl₂) ↓ + 2 HNO₃

Q5 : How to convert Hydrochloric acid to nascent chlorine? Explain with a balanced equation.

Ans: Hydrochloric acid can be converted to nascent chlorine by mixing three parts of concentrated hydrochloric acid and one part of concentrated nitric acid.
Here is the balanced equation:
3HCl (conc) + HNO₃(conc) → NOCL + 2H₂O + 2 [Cl]