Chapter 7: The p Block Elements
NCERT IN TEXT QUESTIONS 7.1. Why are pentahalides more covalent than trihalidcs?Ans: The group 15 elements have 5 e-1 s in their valence shell. It is difficult to lose 3e-1s to form E3+ and even more difficult to lose 5e-1 s to…
Chapter 6: General Principles and Processes of Isolation of Elements
6.1. Which of the ores mentioned can be concentrated by magnetic separation method?Ans: Ores Which are magnetic in nature can be separated from non-magnetic gangue particles by magnetic separation method. For ex: ores of iron such as haemetite…
Chapter 5: Surface Chemistry
NCERT TEXTBOOK QUESTIONS SOLVED 5.1. Write any two characteristics of Chemisorption.Ans: Pt and Pd form inert electrodes, i.e., they are not attacked by the ions of the electrolyte or the products of electrolysis. Hence, they are used as…
Chapter 4: Chemical Kinetics
4.1.For the reaction R—>P, the concentration of reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.Ans. 4.2.In a reaction, 2A…
Chapter 3: Electrochemistry
3.1. How would you determine the standard electrode potential of the system Mg2+1 Mg?Ans: A cell will be set up consisting of Mg/MgSO4 (1 M) as one electrode and standard hydrogen electrode Pt, H, (1 atm)H+/(l M) as second electrode,…
Chapter 2: Solutions
2.1. Calculate the mass percentage of benzene (C6H6) and carbon tetrachloride (CCl4) if 22 g of benzene is dissolved in 122 g of carbon tetrachloride.Ans: Mass of solution = Mass of C6H6 + Mass of CCl4= 22 g+122 g=…
Class 12 Chemistry Chapter 1: The Solid State
1.1. Why are solids rigid?Ans: The constituent particles in solids have fixed positions and can oscillate about their mean positions. Hence, they are rigid. 1.2. Why do solids have definite volume?Ans: Solids keep their volume because of rigidity in…
Chapter 13: Probability
NCERT Solutions for Class 12 Maths Chapter 13 Probability Ex 13.1 Ex 13.1 Class 12 Maths Question 1Given that E and Fare events such thatP (E) = 0.6, P (F) = 0.3 and P(E∩F) = 0.2find P(E|F)…
Error: Contact form not found.
