UNIT-WISE QUESTION BANK

CLASS : 11TH SUBJECT : CHEMISTRY

Unit : 1 Some basic concept of chemistry
1. Explain law of conservation of mass, law of constant composition, law of multiple proportion.
2. What weight of silver nitrate will react with 5.85 gram of sodium chloride to produce 14.35 gram of
silver chloride and 8.5 gram sodium nitrate if the law of conservation of mass is true?
3. When 4.2 g of NaHCO3 is added to solution of acetic acid (CH3COOH) weighing 10.0 g, it is observed
that 2.2 g of CO2 is released into atmosphere. The residue left behind is found to weigh 12.0 g. Show
that these observations are in agreement with the law of conservation of mass.
4. Define molarity, molality and mole fraction.
5. A measured temperature on Fahrenheit scale is 200 °F. What will this reading on Celsius scale?
6. If you land in USA and temperature is 259K, what do you expect cold or hot?
7. How many significant figures in the following numbers pi(𝜋), 0.0045, 1.235, 2.0058, 6.022x1022
8. Define isotope, isobar, isotones and isoelectronic with suitable examples.
9. Calculate average atomic mass of Carbon from the following data:
Isotope Relative abundance (%) Atomic mass (amu)
12
C p1 = 98.892 A1 = 12
13
C p2 = 1.108 A2 = 13.00335
14 -10
C p3 = 2 x 10 A3 = 14.00317
10. Calculate the atomic mass (average) of Chlorine using the following data:
% Natural abundance Molar mass
35
Cl 75.77 34.9689
37
Cl 24.23 36.9659

11. Which isotope of carbon is used for fossil dating in archaeological surveys?
12. Which of the following isotope of oxygen is used for traces of oxygen in biological metabolic activities?
13. Which isotope of hydrogen is radioactive in nature?
14. Which of the following are isoelectronic Na, Mg, Na+, Ne, Ne+.
15. Which of the following pair is isotone in nature?
a) Na & Mg b) Cl & Br c) C & N d) Ne & Ar
16. Give the differences between compound and mixture.
17. Explain the basic postulates of Dalton's atomic theory.
18. Find the molecular mass of the following compounds
a) oxalic acid, c) sucrose,
b) Sodium d) urea,
Hydroxide, e) sulphuric acid.
19. Calculate the percentage composition of various elements in
a) Magnesium Sulphate, c) Sodium sulphate,
b) Potassium chlorate (KClO3), d) Glucose.
20. Calculate the number of molecules in 0.25 moles of oxygen.
21. Find the molarity of solution of 36 gram of glucose (C6H12O6 M = 180) dissolved in 1 L of solution.
22. Calculate the molality of the solute in an aqueous solution containing 23.4 g of NaCl in 100 g of water
23. A sample of 1.325 g of sodium carbonate (Na2CO3 M=106) is dissolved in water and the solution is
made to 250 ml in a volumetric flask. What is the molarity of the resulting solution?
24. 5 gram of ethanol dissolved in 100 ml of solution. Find its molarity and molality (density of solution 0.85
gram/ ml).
 25. An aqueous solution of glucose has mole fraction of solute is 0.6. What will be the value of mole
fraction of solvent?
26. An aqueous solution contains 46% ethanol by mass. Find the mole fraction of ethanol and water in
solution.
27. 90 gram of glucose (C6H12O6) is added to 171 gram of water. Find mole fraction of glucose.
28. Calculate number of molecules in 53 g of Na2CO3.
29. Calculate number of atoms of the constituent elements in 53 g of Na2CO3.
30. Calculate number of moles in 110 g of CO2.
31. Calculate the number of atoms in each of the following
a) 52 moles of helium b) 52 gram of helium
32. A compound contains 4.07% hydrogen, 24.27% carbon and 71.65% chlorine. Its molar mass is 98.96
gram. What is the empirical and molecular formula of the given compound?
33. A compound on analysis was found to contain carbon 34.6 %, hydrogen 3.85 % and rest is oxygen. The
vapour density of compound was 104. Find its empirical formula and molecular formula .
34. An organic compound has 40.69% carbon, 5.10% hydrogen and rest oxygen. The vapour density of
compound is 59. Determine the molecular formula of compound.
35. Balance the following equations:
𝐶𝐻 + 𝑂 → 𝐶𝑂 + 𝐻 𝑂
𝐹𝑒 𝑂 + 𝐻 → 𝐹𝑒 + 𝐻 𝑂
𝑀𝑔 𝑁 + 𝐻 𝑂 → 𝑀𝑔(𝑂𝐻) + 𝑁𝐻
𝐵𝑎𝐶𝑙 + 𝐴𝑙 (𝑆𝑂 ) → 𝐵𝑎𝑆𝑂 + 𝐴𝑙𝐶𝑙
𝑆𝑂 + 𝐻 𝑆 → 𝑆 + 𝐻 𝑂
𝐴𝑙 𝐶 + 𝐻₂𝑂 → 𝐴𝑙(𝑂𝐻) + 𝐶𝐻

Unit : 2 Structure of Atom

1. Who discovered nucleus?
2. Explain Rutherford Model of atom. Give two drawbacks of Rutherford Model.
3. Define wavelength, frequency, Photoelectric effect, black body radiation and electromagnetic spectrum.
4. Write the basic postulates of Planck’s Quantum theory.
5. Write the limitations of Bohr model of atom.
6. Explain dual nature of matter. Derive an expression for the relationship between the wavelength of a
particle and its momentum.
7. Write the maximum number of electrons in third shell (M shell).
8. Write the maximum number of electrons in fourth shell (N shell).
9. Write the maximum number of electrons in second shell (L shell).
10. Explain the following principle:
a) Heisenberg’s uncertainty principle c) Pauli’s exclusion principle
b) Aafbau’s principle d) Hund’s rule of maximum multiplicity
11. Which of the following is correct value for spin quantum number of electron in hydrogen
(a) +1/2 b) -1/2 c) +1 d) -1
12. Which quantum number determines the orientation of orbital?
13. Using s-p-d-f- notation of quantum numbers write the orbital of following Quantum numbers
a) n = 2, l = 0 d) n = 4, l = 2
b) n = 2, l = 1 e) n = 3, l = 2
c) n = 3, l = 0 f) n = 4, l = 1
14. Give differences between orbit and orbital.
15. Write the electronic configuration of following atoms or ions:
Mg, Cu, Cu+, Fe, Fe+2, Fe+3, Mn+2, Ni, S-2
16. The number of electron, proton and neutron present in a species are 10, 12 and 12. Write its symbol.
17. Find the number of unpaired electrons present in phosphorus, chromium and copper after writing the
orbital electronic configuration.
18. 6. Write the symbol of bi-positive ion which contains 12 protons and 10 electrons.
19. Write the name of element that corresponds to each of the following electronic configuration:
i) [Ne] 3s2 3p3 ii) [Ar] 4s2 3d3 iii) [Ne] 3s2 3p5 iv) [Ne] 3s2 3p1
v) [Ar] 4s2 3d7 vi) [Ar] 4s2 3d8 vii) [Ar] 4s1 3d10 vii) [Ar] 4s2 3d5
20. How many nodal planes are present in 3d orbital , 3p orbital and 2s orbital?
21. Out of 3d and 4s orbital which one has more energy?
22. Calculate the frequency of infrared radiation having wavelength 3 x 10 6nanometer.
23. Calculate the wave number of radiation having a frequency of 4x10 14 Hz.
24. What is the number of photons of light with wavelength of 4000 picometre that provide one joule of
energy?
25. Calculate the wavelength in nanometer of the spectral line when the electrons in the hydrogen
spectrum undergo a transition from 4th energy level to second energy level.
26. Calculate the energy of photon transmitted by violet light having wavelength equal to 4000 angstrom.
27. What is the frequency and wavelength of a photon during a transition from n = 5 state to n = 2 state in
hydrogen atom?
28. Calculate the wavelength of the spectral lines obtained in the spectrum of 𝐿𝑖 ion when the transition
takes place between two levels whose sum is 4 and the difference is 2.
29. A certain particle carries 2.5 x 10 𝐶 of electric charge. Calculate the number of electrons present in
it. Find out the atomic number, mass number, number of protons, electrons, and neutrons present in
the element with the notation 92 U238.
30. Calculate the number of electrons, protons and neutrons in 𝑁𝐻 .
31. The number of electrons, protons and neutrons in a species are equal to 18, 16 and 16 respectively.
Assign the proper symbol to the species.
32. The vividh bharti station of All India Radio, Delhi broadcast at a frequency of 1368 KHz (Kilohertz).
Calculate the wave length of the electromagnetic radiation emitted by the transmitter. Which part of
the electromagnetic spectrum does it belongs to?
33. The wavelength range of the visible spectrum extends from Violet (400 nm) to red (750nm). Express
these wavelengths in frequencies (Hz).
34. A 100 watt bulb emits monochromatic light of wavelength 400 nm. Calculate the number of photons
emitted per second by the bulb.
35. Calculate the energy of a mole of photons radiation whose frequency is 5 x 10 𝐻𝑧?
36. (a) Calculate the energy associated with first orbit of He+.
(b) What is the radius of this orbit?
37. What will be the wavelength of a ball of mass 0.1 𝑘𝑔 moving with a velocity of 10 𝑚𝑠 ?
38. Calculate the momentum of a particle having de-Broglie wavelength of 0.1 nm.
39. Show that the circumference of the Bohr orbit for the hydrogen atom is an integral multiple of the de-
Broglie wavelength associated with the electron revolving around the orbit.
40. Similar to electron diffraction, neutron diffraction microscope is also used for the determination of the
structure of molecules. If the wavelength used here is 800 pm; calculate the characteristic velocity
associated with the neutron.
Unit : 3 Classification of elements and periodicity of properties
1. Discuss Mendeleev’s periodic law and modern periodic law.
2. Give the advantages and limitations of modern periodic table.
3. Define periodicity of properties. What is the cause of periodicity of properties?
4. Predict the position(period, group and block) of the following element in periodic table
a) Mg c) Si e) Cr
b) Ar d) N f) Fe
5. Write the IUPAC name of the element whose atomic number is
a) 104 b) 106 c) 107 d) 118
6. What would be the IUPAC name and symbol for the element with atomic number 120?
7. Find the atomic number and symbol of the element if its IUPAC name is (a) unnilunium (b)
Ununquadium.
8. Name the element which belongs to group 2 nd and period 3rd.
9. Name the element which belongs to group 2 nd and period 4th.
10. Name the element which belongs to group 17 and period 3 rd.
11. Name the element which belongs to group 14 and period 2 nd.
12. Identify an element with five electrons in the outer subshell.
13. Identify the element that would tend to lose two electrons.
14. Identify the element that would tend to gain two electrons.
15. Identify the group having metal, nonmetal, liquid as well at room temperature.
16. Define ionic radii. How do ionic radii vary in a group and period of table?
17. Arrange the following species in increasing order of ionic radii.
𝑁 , 𝑂 , 𝐹 , 𝑁𝑎 , 𝑀𝑔 , 𝐴𝑙
18. Define ionization enthalpy. Discuss the factor affecting ionization enthalpy.
19. Define electron gain enthalpy. Discuss the factor affecting electron gain enthalpy.
20. Which is the correct relationship among first three ionization enthalpy of an atom?
a) IE1 > IE2 > IE3 b) IE2 > IE3 > IE1
c) IE3 < IE2 < IE1 d) IE1 < IE2 < IE3
21. Why noble gases have highest ionization enthalpy?
22. Why ionization enthalpy of nitrogen is higher than that of carbon and oxygen?
23. Beryllium and magnesium have zero electron gain affinity. Why?
24. Electron Gain Enthalpy of noble gases is highly positive while Electron Gain Enthalpy of halogen is most
negative. Give reason.
25. Why nitrogen has high ionization enthalpy than that of carbon and oxygen?
26. Would you expect the first ionisation enthalpies for two isotopes of the same element to be same or
different? Justify your answer.
27. Arrange the following atoms in increasing order of ionization enthalpy C, N. O, F, Ne.
28. Which element has highest electronegativity and which has lowest?
29. What are transition elements?
30. What are representative elements?