Chapter 5 Surface Chemistry
Chapter 5 Surface Chemistry NCERT IN-TEXT QUESTIONS Question 1. Why are substances like platinum and palladium often used for carrying out the electrolysis of aqueous solutions ? Answer: The metals like platinum and palladium are used as inert electrodes for carrying out the process of electrolysis because these are not attacked by the ions involved […]
Chapter 4 Chemical Kinetics
Chapter 4 Chemical Kinetics NCERT IN-TEXT QUESTIONS Question 1. For a reaction R → P, the concentration of a reactant changes from 0·03 M to 0·02 M in 25 minutes. Calculate the average rate of the reaction using the units of seconds. Answer: For a reaction, R → P Question 2. In a reaction, 2A […]
Chapter 3 Electrochemistry
Chapter 3 Electrochemistry NCERT IN-TEXT QUESTIONS Question 1. How would you determine the standard electrode potential of the system ; Mg2+ /Mg ? Answer: Question 2. Can you store copper sulphate solution in a zinc pot ? Answer: No, it is not possible. The E° values of the copper and zinc electrodes are as follows […]
Chapter 2 Solutions
Chapter 2 Solutions NCERT IN-TEXT QUESTIONS Question 1. Answer: Question 2. Calculate the mole fraction of benzene in a solution containing 30% by mass of it in carbon tetrachloride. Answer: Let us start with 100 g of the solution in which Mass of benzene = 30 g Mass of carbon tetrachloride = 70 g Molar […]
Chapter 1 The Solid State
Chapter 1 The Solid State NCERT IN-TEXT QUESTIONS Question 1. Why are solids rigid? Answer: Solids are rigid because the constituent particles are very closely packed. They don’t have any translatory movement and can only oscillate about their mean positions. Question 2. Why do solids have a definite volume? Answer: The constituent particles of a […]
Chapter 15 Communication Systems
Chapter 15 Communication Systems Question 1. At which of the following frequency/frequencies the communication will not be reliable for a receiver situated beyond the horizon: (a) 10 kHz (b) 10 MHz (c) 1 GHz (d) 1000 GHz Answer: (b) is correct. Here (c) and (d) frequencies have high penetration power so the earth will absorb them. […]
Chapter 14 Electronics Devices
Chapter 14 Electronics Devices Question 1. In an n-type silicon, which of the following statement is true : (a) Electrons are majority carriers and trivalent atoms are the dopants. (b) Electrons are minority carriers and pentavalent atoms are the dopants. (c) Holes are minority carriers and pentavalent atoms are the doplants. (d) Holes are majority […]
Chapter 13 Nuclei
Chapter 13 Nuclei Question 1. (a) Two stable isotopes of lithium 63Li and 73Li have respective abundance of 7.5% and 92.5%. These isotopes have masses 6.01512 u and 7.01600 u respectively. Find the atomic weight of lithium. (b) Boron has two stable isotopes 105Li and 115Li .Their respective masses are 10.01294 u and 11.00931 u and the atomic weight of boron is 10.811 […]
Chapter 12 Atoms
Chapter 12 Atoms Question 1. Choose the correct alternative from clues given at end of each statement: The size of the atom in Thomson’s model is the atomic size in Rutherford’s model.(much greater than/no different from/much less than.) In the ground state of…………… electrons are in stable equilibrium, while in …………….. electrons always experience a […]
Chapter 11 Dual Nature of Radiation and Matter
Chapter 11 Dual Nature of Radiation and Matter Question 1. Find the (a) maximum frequency, and (b) minimum wavelength of X-rays produced by 30 kV electrons. Answer: Question 2. The work function of caesium metal is 2.14 eV. When light of frequency 6 x 1014 Hz is incident on the metal surface, photo emission of electrons […]