NCERT Solutions for Class 11 Chemistry in PDF form to free download. NCERT Solutions of other subjects based on latest CBSE Curriculum for 2018-19 is also available to free download. Along with NCERT sols, books for revision, assignments – solved and unsolved, notes and special notes for the coming CBSE exams for 2018-19.
NCERT Solutions for Class 11 Chemistry
- Chapter 1: Some Basic Concepts of Chemistry
- Chapter 2: Structure of Atom
- Chapter 3: Classification of Elements and Periodicity in Properties
- Chapter 4: Chemical Bonding and Molecular Structure
- Chapter 5: States of Matter
- Chapter 6: Thermodynamics
- Chapter 7: Equilibrium
- Chapter 8: Redox Reactions
- Chapter 9: Hydrogen
- Chapter 10: The s – Block Elements
- Chapter 11: The p – Block Elements
- Chapter 12: Organic Chemistry – Some Basic Principles and Techniques
- Chapter 13: Hydrocarbons
- Chapter 14: Environmental Chemistry
Law of Chemical Combination
When two or more substances react chemically a compound is formed. The following are the laws which govern the formation of chemical compounds:
Law of Conservation of Mass: “Matter can neither be created nor destroyed.” This law was put forth by Antoine Lavoisier in 1789. This law formed the basis for several later developments in chemistry. In fact this was the result of planned experiments performed by Lavoisier.
Dalton’s Atomic Theory: We know that Dalton’s atomic theory can explain the laws of chemical combination. According to John Dalton (1776 – 1884), “Matter is made up of small indivisible particles.” These smallest indivisible particles are called atoms. Dalton’s atomic theory is helpful to know chemical reaction but during his time the fundamental particles of atom like proton, electron and neutron were not discovered.
Law of Constant Proportion: “A given compound always contains exactly the same proportion of elements by weight.” Joseph Proust (1754 – 1826) observed that samples of cupric carbonate obtained naturally and prepared synthetically in the laboratory had the same percentage composition of elements.
Law of Multiple Proportion: This law was proposed by Dalton in 1803. If two elements can combine to form more than one compound, the mass of one element that combine with a fixed mass of the other element, are in the ration of small whole number.
Law of Combining Weights: According to this law, masses of two elements which separately react chemically with identical masses of a third element are also the masses which react with each other and are in simple multiples of combining weight of an element which is either equal to its atomic weight or simple multiple of it.