.. Solutions Chapter: Quick Revision Q&A Basic Concepts and Concentration Terms Q: Define a solution . A: A homogeneous mixture of two or more chemically non-reacting substances whose composition can be varied within certain limits. Q: What are the two main components of a binary solution ? A: Solute (lesser amount) and Solvent (greater amount). Q: Define Mass Percentage ( %   w / w ). A: Mass of the component in the solution divided by the total mass of the solution, multiplied by 100. Q: Define Molarity ( M ). A: The number of moles of solute dissolved per liter of solution . ( M = Volume of solution in L Moles of solute ​ ). Q: Define Molality ( m ). A: The number of moles of solute dissolved per kilogram of solvent . ( m = Mass of solvent in kg Moles of solute ​ ). Q: Which concentration term is temperature-independent ? A: Molality ( m ) and Mole Fraction ( χ ) , as they involve mass/moles, ...

  Principle of Atom Conservation (POAC): This principle states that the moles of atoms of an element are conserved throughout the reaction. This means, moles of an element in reactants = moles of the element in products. eg. CO + O 2  -----> CO 2 In this moles of C in CO = moles of C in CO 2 This means, moles of CO = moles of CO 2 . Similarly, for O, moles of O in CO + moles of O in O 2  = moles of CO 2 Thus, moles of CO + 2(moles of O 2 ) = 2(moles of CO 2 )   Advantages of Mole Method over other Methods: (1) Balancing of chemical equations is not required in the majority of problems as the method of balancing the chemical equation is based on the principle of conservation of atom conservation.   (2) Number of reactions and their sequences, leading from reactants to products, need not be given.   Note: Whenever balanced chemical equation is given, mole method is very useful. eg. 2KClO 3  -----> 2KCl + 3O 2 Thus, 2(moles of KClO 3 ) = 2(moles of ...