NCERT Solutions for Class 11 Chemistry, Chapter 9 - Hydrogen

In this chapter, you’ll study ‘Hydrogen’ in detail. To your surprise, Hydrogen is the simplest and the lightest of all the chemical elements present on earth. The word Hydrogen is derived from the Greek words ‘hydro’ and ‘genes’ meaning – ‘maker of water or water forming’. It is denoted by the symbol ‘H’, having the atomic number ‘1’. Hydrogen has an atomic weight of 1.008, and it is found in abundance in our universe. It is a tasteless, colourless, odourless and flammable gas. As Hydrogen occurs in diatomic (H2) molecule, it is also known as ‘Dihydrogen’. It is found in abundance in oceans, lakes, rivers, and the atmosphere. Hydrogen is widely used in making ammonia for fertilizers, cyclohexane and methanol. It is also used to hydrogenate oils to form fats and remove sulfur from fuels while refining the oil. Hydrogen is now also seen as a ‘pollution-free’ source of energy and attempt is made to use it extensively.

Thus, an in-depth study of Class 11 Chemistry NCERT Solutions Chapter 9 will give you a good understanding of Hydrogen and its properties in detail.

Let’s take a look at topics and sub-topics of Class 11 Chemistry Chapter 9 – Hydrogen.

9.1 Position of Hydrogen in the Periodic Table

9.2 Dihydrogen, H2

9.2.1 Occurrence

9.2.2 Isotopes of Hydrogen

9.3 Preparation of Dihydrogen, H2

9.3.1 Laboratory Preparation of Dihydrogen

9.3.2 Commercial Production of Dihydrogen

9.4 Properties of Dihydrogen

9.4.1 Physical Properties

9.4.2 Chemical Properties

9.4.3 Uses of Dihydrogen

9.5 Hydrides

9.5.1 Ionic or Saline Hydrides

9.5.2 Covalent or Molecular Hydride

9.5.3 Metallic or Non-stoichiometric (or Interstitial ) Hydrides

9.6 Water

9.6.1 Physical Properties of Water

9.6.2 Structure of Water

9.6.3 Structure of Ice

9.6.4 Chemical Properties of Water

9.6.5 Hard and Soft Water

9.6.6 Temporary Hardness

9.6.7 Permanent Hardness

9.7 Hydrogen Peroxide (H2O2)

9.7.1 Preparation

9.7.2 Physical Properties

9.7.3 Structure

9.7.4 Chemical Properties

9.7.5 Storage

9.7.6 Uses

9.8 Heavy Water, D2O

9.9 Dihydrogen as a Fuel

In Class 11 Chemistry Chapter 9, you will learn –

Section 9.1 – In this section, you’ll learn how Hydrogen is positioned in the periodic table according to its electronic configuration. You’ll also study some interesting characteristics of Hydrogen concerning ionization, metals and halogens.

Section 9.2 – This section deals with the occurrence of Hydrogen, three types of isotopes possessed by hydrogen, atomic and physical properties of Hydrogen.

Section 9.3 – In this section, you’ll observe the methods used in preparing dihydrogen from metals and metal hydrides. You’ll also come across new terms like syngas, coal gasification, water-gas shift reaction and more.

Section 9.4 –  As you proceed ahead in the chapter, this section will highlight the physical and chemical properties of dihydrogen such as reaction with halogens, dioxygen, dinitrogen, metals, metal ions, and metal oxides. You’ll also study some interesting uses of dihydrogen.

Section 9.5 – In this section, you’ll learn what are hybrids and classification of hybrids into three categories.

Section 9.6 – In this section, you’ll acquire knowledge about estimated world water supply, physical properties of water, the structure of water and ice, chemical properties of water, hard and soft water and finally the measures to remove the temporary and permanent hardness of the water.

Section 9.7 – This section deals with the physical properties of hydrogen peroxide, how to prepare hydrogen peroxide, structure and chemical properties of Hydrogen peroxide, how Hydrogen peroxide is stored and its uses.

Section 9.8 – In this section, you’ll acquire knowledge about what is heavy water, its uses, and how to prepare heavy water.

Section 9.9 – The last section will teach you how dihydrogen is used as a fuel; the limitations of dihydrogen; what Hydrogen economy is, and its advantages.

In this chapter, you are provided with several examples with their solutions for a clear understanding of Hydrogen. To know more about NCERT Solutions for Class 11 Chemistry Chapter 9, you should explore the exercises mentioned in this chapter. You can also download the NCERT Solutions for Class 11 Chemistry Chapter 9 PDF, solved by our science experts.