NCERT Exemplar Class 12 Chemistry Chapter 1 Solutions: The Solid State

NCERT Exemplar Class 12 Chemistry Solutions Chapter 1 ‘The Solid State’ is an ideal resource for students currently studying in CBSE Class 12. NCERT Class 12 Chemistry Exemplar Solutions Chapter 1 provides you with clear and detailed answers of the Solid-State Chemistry along with worksheets, exercise assignments that will help you grasp the topic thoroughly. From these solutions, you will have a deeper understanding of the general characteristics of solid-state, about amorphous and crystalline solids, also crystal lattice and unit cell. Apart from these topics, you will also get to learn about their electrical and magnetic properties.

Chapter 1 provides an array of questions with the proper structuring, touching all the concepts of the entire chapter. This chapter has 77 NCERT Exemplar problems in total, grouped into several sections namely: MCQs, Short answer type, matching type, assertion and reason type, and long answer type, etc.

After completing the NCERT textbook, while solving Exemplar problems you sometimes face some tricky questions. In such a time, they would need someone’s help. Instasolv understands the situation and helps you to solve these Exemplar Problems on your own. The objective is to help you understand the exam pattern and the important questions that may come in the CBSE Board exams.

Important Topics for NCERT Exemplar Class 12 Chemistry Solutions Chapter 1

As discussed above, this NCERT Exemplar Solutions for Chapter 1: Solid-State deals with the nature of solids in different temperature and pressure conditions. You will also learn how strong the intermolecular forces exert between their particles, the types of solids and their properties, their crystal lattice structures, packing efficiencies, properties of crystalline and amorphous solids, their correlation in electrical and mechanical properties, and much more. 

Let’s have a look at some of the important topics and definitions for your exam point of view. 

  • Solids:

Before we understand the general characteristics of solid-state, Let’s have a brief overview of solids first. So, you might be familiar with the fact that there are three matters present in this universe named: solids, liquids, and gas, etc. Amongst them, gas and liquids are called fluids, as they can flow. 

But why solids are not considered as fluids? The answer is, because of their particles, exerts an intermolecular force between them. Therefore, they are not able to flow in an available space. Solids are  Rigid and incompressible.

  • General Characteristics of Solid-State:

Let’s have a look at the general characteristics of solid-state are: 

  1. Solids have definite mass, volume, and shape.
  2.  Intermolecular distances between the particles are short.
  3. Intermolecular forces acting between the particles are strong.
  4. They are rigid and incompressible.
  • Crystalline and Amorphous Solids:

As you know, Solids are made up of three types of particles(atoms, molecules, and ions). Due to the arrangement of these particles, Solids are classified into Crystalline and Amorphous types.

Well, Crystalline solids are the types of solids, having large numbers of small crystals based on their constituent particles are arranged in a regular pattern, which means that they have definite geometrical shape. These types of solids melt at a sharp temperature, when they are cut into pieces they acquire a plain and smooth surface. They are anisotropic.

For example- Sodium chloride and quartz.

While, Amorphous Solids are irregular in shape, short-range solids, gradually soften over a range of temperature, supercooled solids and isotropic. Glass, Rubber, and Plastics are the typical examples of it.

  • Classification of  Crystalline solids:

Based on the nature of intermolecular forces present in them, crystalline solids are classified into four categories viz. Molecular, ionic, metallic, and covalent solids. Let us learn about them now:

    1. Molecular Solids- Molecules are constituent particles of it. These solids are further divided into:
      •     Polar molecular solids.
      •     Non-polar molecular solids.
      •     Hydrogen bonded molecular solids.
    1. Ionic Solids –These solids are formed by the 3-D arrangement of ions and are bounded by the strong Coulomb electrostatics forces.
    2. Metallic solids – These solids are formed by metallic bonding in a sea of free electrons.
    3. Covalent solids – These types of solids are formed by the covalent bonding of non-metals in the crystal structures. This type of solids is also termed as giant molecules.
  • Close-packed structures: In solids, the constituted particles are closely packed. Let us see close packing in three dimensions:
    1.  Close packing in one dimension – In 1-dimensional close-packed arrangement, the coordination number is 2.
    2. Close packing in two dimensions – This type of packing can be done in two ways: square close packing and hexagonal close packing. The coordination number is 4.
    3. Close packing in three dimensions – In the 3-dimensional close-packed arrangement, the coordination number is 12
  • Packing efficiency:  Packing efficiency is the percentage of total space filled by the particles
    1. Face centred cubic (fcc) latticeIt has a packing efficiency of 74%                        
    2. Body-centered cubic (bcc) lattice – It has a packing efficiency of 68%
    3. Primitive cubic (pc) lattice – Primitive cubic (pc) lattice’s  packing efficiency is 52.4%

Discussion of Exercises of NCERT Exemplar Class 12 Chemistry solutions Chapter 1: Solid-State

  • The first set of NCERT Exemplar problems and solutions for CBSE Class 12 are of MCQ types. They are further divided into MCQ1 and MCQ2. The first type contains 37 Exemplar problems while type 2 consists of 16 questions. These questions are simple and easy to answer and you need to pick one correct choice among 4 options.
  • MCQ sections will judge your knowledge on almost all the topics associated with it. Most of the NCERT Exemplar problems require a thorough understanding of the properties of crystalline and amorphous solids. Some questions also use concepts like Schottky, Frenkel defects, semiconductors, and crystal lattice structure, etc.
  • The second set of questions are of short answer types, containing 10 NCERT Exemplar problems. These questions will brush up your knowledge on the concepts of semiconductors, crystal lattice structures, about general characteristics of solids, etc.
  • The third set of questions are of a matching type. This section has 5 NCERT Exemplar problems. It has two columns, you have to match the correct answer accordingly. Questions are generally from stoichiometric defects, unit cells, and close-packed structures.
  • The next set of questions are of assertion and reason type. It has 5 NCERT Exemplar problems. In the following questions, a statement of assertion followed by a statement of reason is given. You have to choose the correct one out.
  • The fourth and the last section is long answer type questions. This section contains 4 NCERT Exemplar problems. These questions need a deeper understanding of the concepts like stoichiometric defects, cubic close-packed structures, semiconductors, etc.

 Why Use NCERT Exemplar Class 12 Chemistry Solutions Chapter 1 by Instasolv?

NCERT Exemplar Class 12 Solutions for Chemistry Chapter 1 by Instasolv can be the right source of preparation for the students aspiring to their career goals in different entrance examinations like JEE mains and NEET. 

Like Maths and Physics, the Chemistry section is also important to outperform in various competitive examinations. The solutions at Instasolv are free of cost and easy for you to access. 

Our experts have provided the solutions in a detailed manner. Practising these NCERT Exemplar problems daily will boost your confidence level and help in managing the time management skills as well.