Complete Solutions for NCERT Chemistry Class 12 Intext Questions Chapter 2

ncert chemistry class 12 intext questions solutions chapter 2 provides detailed solutions to all intext questions. Learn step-by-step explanations for better understanding.

Question 1:
What is the difference between the molecular mass and molar mass?

Answer:
Molecular mass is the mass of a single molecule, while molar mass refers to the mass of one mole of a substance, expressed in grams per mole. Molar mass is numerically equal to molecular mass but is expressed in grams per mole.

Question 2:
How do you calculate the empirical formula of a compound?

Answer:
The empirical formula is determined by finding the simplest whole number ratio of atoms of each element in the compound. To find it, divide the number of moles of each element by the smallest number of moles present and adjust to the nearest whole number.

Question 3:
What is an isotope?

Answer:
Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. This results in different atomic masses but the same chemical properties.

Question 4:
Why is the atomic mass of chlorine often written as 35.5?

Answer:
Chlorine has two stable isotopes, chlorine-35 and chlorine-37. The atomic mass of chlorine is the weighted average of these isotopes, leading to a value of approximately 35.5.

Question 5:
What is the significance of the mole concept in chemistry?

Answer:
The mole concept allows chemists to count atoms, molecules, and ions by weighing a known quantity of a substance. It bridges the gap between the atomic scale and the macroscopic world.

Question 6:
How is the volume of a gas related to its temperature and pressure?

Answer:
The volume of a gas is directly proportional to its temperature and inversely proportional to its pressure. This relationship is described by the ideal gas law: PV = nRT.

Question 7:
What is the law of conservation of mass?

Answer:
The law of conservation of mass states that mass is neither created nor destroyed in a chemical reaction. The total mass of the reactants is always equal to the total mass of the products.

Question 8:
How does the concept of oxidation and reduction apply to redox reactions?

Answer:
In redox reactions, oxidation involves the loss of electrons, while reduction is the gain of electrons. These reactions always occur together, as one substance loses electrons and another gains them.

Question 9:
What is the difference between an ionic bond and a covalent bond?

Answer:
In an ionic bond, electrons are transferred from one atom to another, resulting in positively and negatively charged ions. In a covalent bond, electrons are shared between atoms.

Question 10:
What is meant by a solution being saturated?

Answer:
A saturated solution contains the maximum amount of solute that can dissolve at a given temperature and pressure. Any additional solute added will not dissolve.

Question 11:
What are the characteristics of acids and bases according to the Arrhenius theory?

Answer:
According to the Arrhenius theory, acids produce hydrogen ions (H⁺) in aqueous solutions, while bases produce hydroxide ions (OH⁻) when dissolved in water.

Question 12:
Explain the concept of molarity and how it is calculated.

Answer:
Molarity is a measure of the concentration of a solute in a solution. It is calculated as the number of moles of solute divided by the volume of solution in liters.

Question 13:
What is meant by the term ‘solubility product’?

Answer:
The solubility product (Ksp) is an equilibrium constant that represents the solubility of a salt in water. It is the product of the concentrations of the ions in a saturated solution, each raised to the power of its coefficient in the dissociation equation.

Question 14:
How do you determine the pH of a solution?

Answer:
The pH of a solution is determined by taking the negative logarithm of the concentration of hydrogen ions in the solution, expressed as pH = -log[H⁺].

Question 15:
What is the difference between a strong acid and a weak acid?

Answer:
A strong acid dissociates completely in water to give a high concentration of hydrogen ions, while a weak acid only partially dissociates, resulting in a lower concentration of hydrogen ions.

Question 16:
What is the principle of the law of definite proportions?

Answer:
The law of definite proportions states that a chemical compound always contains the same elements in the same proportion by mass, regardless of the quantity or source of the compound.

Question 17:
What are the properties of an ideal gas?

Answer:
An ideal gas is a hypothetical gas that perfectly follows the ideal gas law. It has no intermolecular forces, and its particles are in constant, random motion, with elastic collisions.

Question 18:
Explain the term ‘empirical formula’.

Answer:
The empirical formula represents the simplest whole-number ratio of elements in a compound. It does not necessarily reflect the actual number of atoms in a molecule, which is shown by the molecular formula.

Question 19:
What does the term ‘molar volume’ mean?

Answer:
Molar volume is the volume occupied by one mole of a substance, typically a gas, at standard temperature and pressure (STP). For ideal gases, the molar volume is 22.4 liters.

Question 20:
What is a limiting reagent in a chemical reaction?

Answer:
The limiting reagent is the reactant that is completely consumed first in a chemical reaction, limiting the amount of product formed.

Question 21:
What is the significance of the atomic number?

Answer:
The atomic number is the number of protons in the nucleus of an atom and determines the element's identity. It also defines the position of the element in the periodic table.

Question 22:
How are the atomic masses of elements determined?

Answer:
Atomic masses are determined by comparing the mass of an element’s atom to the mass of a carbon-12 atom, with the atomic mass unit (amu) being defined as one twelfth of the mass of a carbon-12 atom.

Question 23:
What are the trends in atomic size across a period and down a group?

Answer:
Across a period, atomic size decreases because the number of protons increases, pulling electrons closer to the nucleus. Down a group, atomic size increases due to additional electron shells.

Question 24:
Explain the concept of a redox reaction with an example.

Answer:
A redox reaction involves the transfer of electrons between two substances. For example, when hydrogen reacts with oxygen to form water, hydrogen is oxidized (loses electrons) and oxygen is reduced (gains electrons).

Question 25:
What is the role of a catalyst in a chemical reaction?

Answer:
A catalyst speeds up a chemical reaction by lowering the activation energy required for the reaction to proceed, without being consumed in the reaction.

Question 26:
What is meant by the term 'molarity' in terms of solution concentration?

Answer:
Molarity refers to the concentration of a solute in a solution, expressed as the number of moles of solute per liter of solution.

Question 27:
What is the formula for calculating the percentage composition of a compound?

Answer:
The percentage composition is calculated by dividing the mass of each element in the compound by the total molar mass of the compound, then multiplying by 100.

Question 28:
What is the difference between an endothermic and exothermic reaction?

Answer:
In an endothermic reaction, energy is absorbed from the surroundings, while in an exothermic reaction, energy is released to the surroundings.

Question 29:
What is the effect of temperature on the solubility of solids in liquids?

Answer:
Generally, the solubility of solids in liquids increases with an increase in temperature. However, there are exceptions depending on the substance.

Question 30:
What is meant by the term 'enthalpy'?

Answer:
Enthalpy is the total heat content of a system, which includes both internal energy and the energy required to displace the environment to make room for the system.

Question 31:
What are the different types of chemical bonds?

Answer:
Chemical bonds can be classified as ionic bonds, covalent bonds, and metallic bonds, depending on how the electrons are shared or transferred between atoms.

Question 32:
What is the relationship between pressure and volume in Boyle's law?

Answer:
Boyle's law states that the pressure of a gas is inversely proportional to its volume when the temperature and amount of gas are kept constant.

Question 33:
What is the atomic model of Bohr?

Answer:
Bohr’s atomic model suggests that electrons orbit the nucleus in fixed energy levels without radiating energy. The electron can jump between levels by absorbing or emitting a quantum of energy.

Question 34:
How are acids and bases defined according to the Bronsted-Lowry theory?

Answer:
According to the Bronsted-Lowry theory, acids are proton donors, while bases are proton acceptors.

Question 35:
What is a neutralization reaction?

Answer:
A neutralization reaction occurs when an acid reacts with a base to form water and a salt. This reaction typically results in the pH of the solution moving closer to 7.

Question 36:
What is meant by molar heat capacity?

Answer:
Molar heat capacity is the amount of heat required to raise the temperature of one mole of a substance by one degree Celsius.

Question 37:
What is the atomic mass unit (amu)?

Answer:
The atomic mass unit (amu) is a unit of mass used to express atomic and molecular weights. One amu is defined as one twelfth the mass of a carbon-12 atom.

Question 38:
What is the difference between a covalent bond and a coordinate bond?

Answer:
In a covalent bond, electrons are shared between two atoms. In a coordinate bond, one atom provides both electrons for the bond.

Question 39:
What is an ionization energy?

Answer:
Ionization energy is the energy required to remove an electron from a neutral atom in its gaseous state.

Question 40:
What is the significance of Avogadro’s number?

Answer:
Avogadro’s number, 6.022 × 10²³, is the number of particles (atoms, molecules, or ions) in one mole of a substance.

Question 41:
How does the concept of ‘chemical equilibrium’ apply to reversible reactions?

Answer:
In a reversible reaction, chemical equilibrium is reached when the rate of the forward reaction equals the rate of the reverse reaction, and the concentrations of reactants and products remain constant.

Question 42:
What are the characteristics of a chemical reaction?

Answer:
Chemical reactions involve the rearrangement of atoms and the breaking and forming of chemical bonds, resulting in the production of new substances.

Question 43:
What is the significance of the periodic table in understanding elements?

Answer:
The periodic table arranges elements based on their atomic numbers, providing a systematic framework to study their properties, relationships, and trends.

Question 44:
What is meant by the term ‘activation energy’?

Answer:
Activation energy is the minimum energy required for a chemical reaction to occur. It is the energy needed to break bonds in the reactants.

Question 45:
What is a colloidal solution?

Answer:
A colloidal solution is a mixture in which particles of one substance are dispersed throughout another substance but do not settle out.

Question 46:
How is energy released in exothermic reactions?

Answer:
Energy is released in exothermic reactions as new bonds are formed, which results in the production of energy in the form of heat or light.

Question 47:
What is the importance of the pH scale in chemistry?

Answer:
The pH scale measures the acidity or basicity of a solution, ranging from 0 (acidic) to 14 (basic), with 7 being neutral.

Question 48:
How does the principle of conservation of energy apply to chemical reactions?

Answer:
The principle of conservation of energy states that energy cannot be created or destroyed in a chemical reaction, but it can change forms, such as from chemical potential energy to heat.

Question 49:
What is a dynamic equilibrium in a chemical reaction?

Answer:
A dynamic equilibrium occurs when the forward and reverse reactions in a reversible reaction occur at the same rate, leading to no net change in the concentration of reactants and products.

Question 50:
What are the factors that affect the rate of a chemical reaction?

Answer:
The rate of a chemical reaction is affected by factors such as temperature, concentration of reactants, surface area, and the presence of a catalyst

Recommended Indian Books for NCERT Chemistry Class 12 Intext Questions Solutions Chapter 2

NCERT Chemistry Textbook for Class 12
Author: NCERT
Publication: NCERT
Content: This textbook contains all the intext questions for Chapter 2 along with the corresponding solutions. It focuses on building conceptual clarity in topics such as solutions, types of solutions, solubility, and Raoult’s law.

Physical Chemistry for Class 12
Author: O.P. Tandon
Publication: G.R. Bathla Publications
Content: A highly detailed book that explains key concepts in physical chemistry. This book provides in-depth solutions to the NCERT intext questions and elaborates on important topics like molarity, molality, and the types of solutions.

Modern Approach to Chemical Calculations
Author: R.C. Mukherjee
Publication: Krishna Prakashan
Content: This book is known for its clarity in solving numerical problems related to molarity, normality, and Raoult’s law. It is especially helpful for practicing the solutions of intext questions involving quantitative aspects of chemistry.

Concise Inorganic Chemistry
Author: J.D. Lee
Publication: Wiley India
Content: Though primarily focused on inorganic chemistry, this book helps reinforce the understanding of concepts in Chapter 2. It provides solutions to questions and discusses the chemical behavior of various substances in solutions.

Physical Chemistry – A Textbook for Class 12
Author: N. Awasthi
Publication: G.R. Bathla Publications
Content: This book provides solutions to the NCERT intext questions and explains the applications of molarity, molality, and other concepts from Chapter 2 in a comprehensive manner.

Chemistry for Class 12
Author: Cengage Learning
Publication: Cengage
Content: This book provides detailed explanations of each concept covered in Chapter 2, followed by a section of practice questions similar to NCERT intext questions, aiding in better concept retention.

New Pattern Chemistry for Class 12
Author: O.P. Agarwal
Publication: New Age International
Content: This book covers both theoretical and numerical aspects, providing solutions to all intext questions and helping students understand the relationship between the theory and its real-life applications.

Advanced Problems in Physical Chemistry
Author: J.D. Lee
Publication: Wiley India
Content: A reference book that provides detailed solutions for advanced problems, perfect for students seeking additional problems to practice after completing the NCERT solutions for Chapter 2.

Objective Physical Chemistry
Author: R.K. Gupta
Publication: Arihant Publications
Content: This book focuses on objective-type questions, including those based on the content of Chapter 2. It offers a wide range of problems, allowing students to test their understanding of the chapter.

Chemistry Class 12 – NCERT Exemplar Problems & Solutions
Author: NCERT
Publication: NCERT
Content: This book provides a collection of problems and solutions that align with the NCERT curriculum, offering additional exercises to support Chapter 2 learning. It is great for extra practice and understanding complex problems.

Practical Chemistry for Class 12
Author: B.B. Lal
Publication: S. Chand Publications
Content: While this book focuses primarily on practical chemistry, it includes relevant intext question solutions related to solutions and solubility, bridging the gap between theoretical concepts and practical applications.

Chemistry for Class 12
Author: L.G. Wade
Publication: Pearson
Content: Wade’s book simplifies complex chemistry topics and provides detailed solutions for the intext questions of Chapter 2, enhancing students’ understanding of solutions and their behavior.

Fundamentals of Chemistry
Author: B.R. Puri
Publication: Vishal Publishing
Content: This book covers key concepts from Chapter 2, including solution formation and the properties of solutions. The solutions are explained step-by-step, making it a great resource for clear understanding.

Chemistry Class 12 - Full Marks
Author: Full Marks Publications
Publication: Full Marks
Content: A student-friendly book with concise explanations, the Full Marks series provides solutions to Chapter 2 in a clear, easy-to-understand format. It includes both theory and practical problem-solving strategies.

NCERT Solutions Chemistry Class 12
Author: R.S. Aggarwal
Publication: S. Chand Publications
Content: This book provides direct solutions to the NCERT intext questions, making it a convenient reference for students seeking quick solutions and explanations to Chapter 2’s exercises.

Organic Chemistry – For Class 12
Author: R. K. Gupta
Publication: Arihant Publications
Content: A comprehensive guide that includes organic chemistry concepts, and solutions to the intext questions, particularly in the context of solution chemistry and molecular interactions.

IIT Chemistry for Class 12
Author: R.K. Sharma
Publication: Arihant Publications
Content: Designed for competitive exam preparation, this book provides a robust collection of practice questions related to NCERT Chapter 2, ensuring students can apply theoretical knowledge to practical problems.

Essential Chemistry Class 12
Author: S.K. Jain
Publication: Dhanpat Rai
Content: Essential Chemistry explains fundamental concepts of chemistry, including solutions, solubility, and colligative properties, all of which are covered in detail in Chapter 2.

Objective Chemistry Class 12
Author: R.D. Sharma
Publication: Dhanpat Rai Publications
Content: Focused on multiple-choice questions and short-answer questions, this book helps students practice the NCERT intext questions while preparing for exams.

Chemistry for Class 12 (Volume 1)
Author: N.K. Singh
Publication: Saraswati House
Content: This book explains core concepts in solutions chemistry, providing clear explanations and a wide range of questions and answers that mirror the NCERT intext questions for Chapter 2.

NCERT Chemistry Class 12 Intext Questions Solutions Chapter 2: An Expert Guide

NCERT Chemistry for Class 12 Chapter 2 is a crucial section that deals with solutions—a concept fundamental to understanding the behavior of substances when dissolved in liquids. This chapter delves deep into various types of solutions, their properties, and the laws governing their behavior. For students, solving the intext questions in this chapter can be a key to mastering the topic. These questions challenge students to apply theoretical concepts and solidify their grasp of physical chemistry.

The intext questions in this chapter mainly focus on molarity, molality, Raoult’s law, types of solutions, and factors affecting solubility. In solving these questions, students need to understand the interplay between different types of solutions—whether saturated or unsaturated—and their concentration terms such as mole fraction and molarity. For example, students are often asked to calculate the concentration of a solution given specific data, test their knowledge on the laws like Raoult’s Law, or explore the solubility factors that influence the dissolution process.

One of the significant aspects of Chapter 2 is understanding the concept of colligative properties, which include boiling point elevation, freezing point depression, osmotic pressure, and vapor pressure lowering. Intext questions often involve calculating changes in these properties when different solutes are dissolved in solvents. Such problems help students connect theoretical knowledge to practical applications, preparing them for both exams and real-world chemical processes.

It’s essential for students to engage with the solutions to these intext questions. By doing so, they not only reinforce their learning but also build problem-solving skills crucial for exams. These solutions are carefully structured to follow a logical approach, guiding students step-by-step to ensure they understand each concept thoroughly.

Understanding how to solve these questions also prepares students for higher-level topics and competitive exams, where concepts from Chapter 2 are frequently tested. Mastery over topics like molarity, molality, and colligative properties, along with a deep understanding of solution dynamics, will set a strong foundation for future studies in chemistry.

The solutions provided in various books like O.P. Tandon’s "Physical Chemistry for Class 12" and J.D. Lee’s "Concise Inorganic Chemistry" complement the NCERT curriculum by offering more detailed explanations and additional practice problems. These books break down complex concepts into simpler terms and provide an extensive set of problems that cater to different difficulty levels.

Incorporating these solutions into daily study routines helps students gain confidence and clarity on how to approach chemistry problems efficiently.