C.B.S.E Solution

Redox Reactions NCERT Exercises Question 1.Assign oxidation number to the underlined elements in each of the following species :(a) NaH2PO4(b) NaHSO4(c) H4P2O7(d) K2MnO4(e) CaO2(f) NaBH4(g) H2S2O7(h) KAI(SO4)2.12H2O Solution.Let the oxidation no. of underlined element in all the given compounds = x Question 2.What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?(a) KI3(b) H2S4O6(c) Fe3O4(d) CH3CH2OH(e) CH3COOH […]

Equilibrium NCERT Exercises Question 1.A liquid is in equilibrium with its vapor in a sealed container at a fixed temperature. Thevolume of the container is suddenly increased.(a) What is the initial effect of the change on vapor pressure?(b) How do rates of evaporation and condensation change initially?(c) What happens when equilibrium is restored finally and what will be

Thermodynamics NCERT Exercises Question 1.Choose the correct answer. A thermodynamic state function is a quantity(a) used to determine heat changes(b) whose value is independent of path(c) used to determine pressure volume work(d) whose value depends on temperature only. Solution.(b): State function is a property of the system whose value depends only upon the state of the system and is independent

States of Matter Question 1.What will be the minimum pressure required to compress 500 dm3 of air at 1 bar to 200 dm3 at 30°C? Solution.According to Boyle’s law, at constant temperature, Question 2.A vessel of 120 mL capacity contains a certain amount of gas of 35°C and 1.2 bar pressure. The gas is transferred to another

Chemical Bonding and Molecular Structure Question 1.Explain the formation of a chemical bond. Solution.The attractive force which holds various constituents (atoms, ions, etc.) together in different chemical species is called a chemical bond. The formation of chemical compounds takes place as a result of combination of atoms in different ways. The atoms interact with each

Classification of Elements and Periodicity in Properties NCERT Exercises Question 1.What is the basic theme of organization in the periodic table? Solution.By 1865, number of identified elements was 63 and with such a large number of elements it was very difficult to study individually the chemistry of all these elements and their innumerable compounds individually.

Structure of The Atom Question 1.(i) Calculate the number of electrons which will together weigh one gram.(ii) Calculate the mass and charge of one mole of electrons. Solution. Question 2.(i) Calculate the total number of electrons present in one mole of methane.(ii) Find (a) the total number and (b) the total mass of neutrons in 7 mg of 14C. (Assume that mass of a

Some Basic Concepts of Chemistry Question 1.Calculate the molecular mass of the following :(i) H2o(ii) CO2(iii) CH4 Solution:(i) Molecular mass of H2O :2 × 1 + 1 × 16 = 18u(ii) Molecular mass of CO2 :1 × 12 + 2× 16 = 44 u(iii) Molecular mass of CH4 : 12 + 4 × 1 = 16 u Question 2.Calculate the mass percent of