NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom

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NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom

Q1. Which of the following conclusions could not be derived from Rutherford’s α-particle scattering experiment?
(a) Most of the space in the atom is empty.
(b) The radius of the atom is about 10 -10 m while that of nucleus is 10 -15
(c) Electrons move in a circular path of fixed energy called orbits.
(d) Electrons and the nucleus are held together by electrostatic forces of attraction.

Sol: (c) The concept of circular paths of fixed energy was proposed by Bohr and not derived from Rutherford’s scattering experiment.

Q2. Which of the following options does not represent ground state electronic configuration of an atom?

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom

Sol: (b) Correct configuration in ground state should be 1 s2 2s2 2p6 3s2 3pb3d104s1

Q3. The probability density plots of Is and 2s orbitals are given in the following figures.
NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-1

The density of dots in a region represents the probability density of finding electrons in the region.On the basis of the above diagram, which of the following statements is incorrect?
(a) 1s and 2s orbitals are spherical in shape.
(b) The probability of finding the electron is maximum near the nucleus.
(c) The probability of finding the electron at a given distance is equal in all directions.
(d) The probability density of electrons for 2s orbital decreases uniformly as distance from the nucleus increases.
Sol: (d) The probability density of electrons for 2s orbital first increases then decreases and after that it begins to increase again.

Q4. Which of the following statements is not correct about the characteristics of cathode rays?
(a) They start from the cathode and move towards the anode.
(b) They travel in straight line in the absence of an external electrical or magnetic field.
(c) Characteristics of cathode rays do not depend upon the material of electrodes in cathode ray tube.
(d) Characteristics of cathode rays depend upon the nature of gas present in the cathode ray tube.
Sol:(d) Cathode rays consist of negatively charged material particles called electron. They were discovered by William Crookes. The characteristics of cathode rays do not depend upon the material of electrodes and the nature of the gas present in the cathode ray tube.

Q5. Which of the following statements about the electron is incorrect?
(a) It is a negatively charged particle.
(b) The mass of electron is equal to the mass of neutron.
(c) It is a basic constituent of all atoms.
(d) It is a constituent of cathode rays.
Sol: (b) The mass of electron is very small as compared to the mass of the neutron. Mass of electron = 9.1 x 10-31 kg Mass of neutron = 1.674 x 10-27 kg

Q6. Which of the following properties of atom could be explained correctly by Thomson Model of atom?
(a) Overall neutrality of atom.
(b) Spectra of hydrogen atom.
(c) Position of electrons, protons and neutrons in atom.
(d) Stability of atom.
Sol: (a) According to Thomson model of atom, the mass of the atom is assumed to be uniformly distributed over the atom. This model was able to explain the overall neutrality of the atom.

Q7. Two atoms are said to be isobars if
(a) they have same atomic number but different mass number.
(b) they have same number of electrons but different number of neutrons.
(c) they are same number of neutrons but different number of electrons.
(d) Sum of the number of protons and neutrons is same but the number of protons is different.
Sol: (d) Isobars have different atomic number, i.e., number of protons but same mass number, i.e., sum of number of protons and neutrons.

Q8. The number of radial nodes for 3p orbital is .
(a) 3 (b) 4 (c) 2 (d) 1
Sol: (d) Number of radial nodes = n-1 – 1
For 3p orbital, n = 3 – 1 – 1 = 1
Number of radial nodes = 3 – 1 – 1 = 1

Q9. Number of angular nodes for 4d orbital is __________ .
(a) 4 (b) 3 (c) 2 (d) 1
Sol: (c) Number of angular nodes in 4d orbital = l = 2

Q10. Which of the following is responsible to rule out the existence of definite paths or trajectories of electrons?
(a) Pauli’s exclusion principle
(b) Heisenberg’s uncertainty principle
(c) Hund’s rule of maximum multiplicity
(d) Aufbau principle
Sol: (b) According to Heisenberg’s uncertainty principle, the position and velocity of an electron cannot be determined simultaneously with accuracy which rules out the existence of fixed paths.

Q11. Total number of orbitals associated with third shell will be _______.
(a) 2
(b) 4
(c) 9
(d) 3
Sol: (c) No of orbitals in 3rd shell (n = 3) = n2 = 32 = 9.

Q12. Orbital angular momentum depends on
(a) l
(b) n and l
(c) n and m
(d) m and s

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-2

Q13. Chlorine exists in two isotopic forms, Cl-37 and Cl-35, but its atomic mass is 35.5. This indicates the ratio of Cl-37 and Cl-35 is approximately
(a) 1 : 2
(b) 1 : 1
(c) 1:3
(d) 3:1

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-3
Q14. The pair of ions having same electronic configuration is _______

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-4

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-5

Q15. For the electrons of oxygen atom, which of the following statements is correct?

(a) Zeff for an electron in a 2s orbital is the same as Zeff for an electron in a 2p
(b) An electron in the 2s orbital has the same energy as an electron in the 2p
(c) Zeff for an electron in Is orbital is the same as Zeff for an electron in a 2s orbital.
(d) The two electrons present in the ?s orbital have spin quantum numbers ms but of opposite sign.
NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-6

Q16. If traveling at same speeds, which of the following matter waves have the shortest wavelength?
(a) Electron
(b) Alpha particle (He2- )
(c) Neutron           
(d) Proton

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-7

More than One Correct Answer Type

Q17. Identify the pairs which are not of isotopes?

Q18. Out of the following pairs of electrons, identify the pairs of electrons present in degenerate orbitals:
(a) (i) n = 3, l = 2, ml = -2, ms = -1/2
(ii) n = 3, l= 2, ml = -1, ms = -1/2
(b) (i) n = 3, l = 1,  ml = 1,    ms = +1/2
(ii)     n =  3, l = 2,  ml = 1,   ms = +1/2
(c) (i) n = 4, l = 1,  ml = 1,  ms = +1/2
(ii) n =  3, l = 2,  ml = 1,   ms = +1/2
(d) (i) n = 3, l = 2, ml = +2, ms = -1/2
(ii)n = 3, l = 2, ml = +2, ms = +1/2

Sol: (a, d) Degenerate orbitals mean the orbitals of the same sub-shell of the same main shell, i.e., their n and l values are the same. Other two pairs have different values of n and l hence, cannot be having the same energy.

Q19. Which of the following sets of quantum numbers are correct?

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-8

Sol: (b, c) If n = 1, l ≠ 1. Hence, (a) is wrong.
If n = 2, l= 0, 1. For l = 1, m = -1, 0, +1. Hence (b) is correct.
If n = 3, l= 0, 1,2. For l = 2, m = -2, -1, 0, +1, +2. Hence (c) is correct.
If n = 3, l ≠4. Hence, (d) is wrong.

Q20. In which of the following pairs, the ions are isoelectronic?

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-9

Q21. Which of the following statements concerning the quantum numbers are correct?
(a) Angular quantum number determines the three dimensional shape of the orbital.
(b) The principal quantum number determines the orientation and energy of the orbital.
(c) Magnetic quantum number determines the size of the orbital.
(d) Spin quantum number of an electron determines the orientation of the spin of electron relative to the chosen axis.
Sol: (a, d)
(a) Azimuthal quantum number l is also known as orbital angular momentum or subsidiary quantum number. It determines three-dimensional shape of the orbital.
(b) The principal quantum number determines the size of the orbit.
(c) Magnetic quantum number determines the orientation of the electron cloud in a subshell.
(d) An electron spins around its own’ axis, much in a similar way as earth spins around its own axis while revolving around the sun. In other words, an electron has, besides charge and mass, intrinsic spin angular quantum number.

Short Answer Type Questions
Q22. Arrange s, p and d sub-shells of a shell in the increasing order of effective nuclear charge (Zeff) experienced by the electron present in them
Sol: .s-orbitals shield the electrons from the nucleus more effectively than p-orbitals which in turn shield more effectively than d-orbitals. Hence, the arrangement of subshells in the increasing order of effective nuclear charge is:
d<p< s

Q23. Show the distribution of electrons in oxygen atom (atomic number 8) using orbital diagram.

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-10

Q24. Show the distribution of electrons in oxygen atom (atomic number 8) using orbital diagram.

Sol: Ni (28): ls2 2s2 2p6 Is2 3p6 3d8 4s2
Ni2+ (26): Is2 2s2 2p6 3s2 3p6 3d8
Hence, to form Ni2+ ion, it will lose 2 electrons from 4s orbital.

Q25. Which of the following orbitals are degenerate?
3dxy, 4dxv, 3dyz, 3dz2:, 4dyz., 4dz2:

Sol: Degenerate orbitals are the orbitals of the same subshell of the same main shell. Hence, these are
(3dxy, 3d z2, 3dyz) and (4dxy, 4dxz, 4d z2).

Q26. Calculate the total number of angular nodes and radial nodes present in 3p orbital.
Sol:For 3p orbital, n = 3,l= 1
Number of angular nodes = 1=1
Number of radial nodes = n — l —1 = 3—1 — 1 = 1
Q27. The arrangement of orbitals on the basis of energy is based upon their (n +l) value. Lower the value of (n + l), lower is the energy. For orbitals having the same values of (n + I), the orbital with lower value of n will have lower energy.
I. Based upon the above information, arrange the following orbitals in the increasing order of energy.
(a) 1s, 2s, 3s, 2p
(b) 4s, 3s , 3p, 4d
(c) 5p, 4d, 5d, 4f, 6s
(d) 5f, 6d , 7s , 7p
II. Based upon the above information, solve the questions given below:
(a) Which of the following orbitals has the lowest energy?
4d, 4f, 5s, 5p
(b) Which of the following orbitals has the highest energy?
5p, 5d, 5f 6s, 6p

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-11

Q28. Which of the following will not show deflection from the path on passing through an electric field?
Proton, cathode rays, electron, neutron.
Sol: Neutron, since it is neutral and cannot be deflected by an electric field.

Q29. An atom having atomic mass number 13 has 7 neutrons. What is the atomic number of the atom?
Sol: Atomic mass number = A = 13. n = 7
As A = n + p p = A — n= 13 —7 = 6
Hence Z = p = 6

Q30. Wavelengths of different radiations are given below:

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-11

Q31. The electronic configuration of valence shell of Cu is 3d10 4s 1 and not 3d94s2. How is this configuration explained?
Sol: Configuration with completely filled and half-filled orbitals have extra stability. In 3d104s1, d-orbitals are completely filled and s-orbital is half- filled. Hence, it is a more stable configuration.

Q32. The Balmer series in the hydrogen spectrum corresponds to the transition from n1 = 2 to n2 = 3, 4,……… This series lies in the visible region. Calculate the wave number of line associated with the transition in Balmer series when the electron moves to n = 4 orbit. (RH = 109677 cm-1).
NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-12

Q33. According to de Broglie, matter should exhibit dual behaviour, that is both particle and wave like properties. However, a cricket ball of mass 100 g does not move like a wave when it is thrown by a bowler at a speed of 100 km/h. Calculate the wavelength of the ball and explain why it does not show wave nature.

NCERT Exemplar Class 11 Chemistry Chapter 2 Structure of Atom-13

Since the wavelength is very small, the wave nature cannot be detected.

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Periodic Table of Elements

How to Learn Periodic Table

How is the periodic table of the elements arranged?

Arrangement of elements in the Periodic Table

Figure shows the Periodic Table in use today.

Periodic Table of Elements

Elements are arranged horizontally In ascending order of their proton numbers, from 1 to 116, in the Periodic Table.

Groups

  • Definition: Each vertical column of elements in the Periodic Table is known as a group.
  • Elements with the same number of valence electrons are arranged in the same group.
  • There are 18 vertical columns of elements in the Periodic Table known as Group 1, Group 2, until Group 18.
    • Group 1 elements are known as alkali metals.
    • Group 2 elements are known as alkaline earth metals.
    • Group 3 to Group 12 elements are known as transition elements.
    • Group 17 elements are known as halogens.
    • Group 18 elements are known as noble gases.

Periods

  • Definition: Each horizontal row of elements in the Periodic Table is known as a period.
  • There are 7 horizontal rows of elements in the Periodic Table, known as Period 1, Period 2, until Period 7.
  • Periods 1 to 3 are short periods while Periods 4 to 7 are long periods.
    • Period 1 contains 2 elements.
    • Periods 2 and 3 contain 8 elements respectively.
    • Periods 4 and 5 contain 18 elements respectively.
    • Period 6 contains 32 elements.
    • Period 7 contains 27 elements.
  • Although Period 6 contains 32 elements, elements with proton numbers 57 to 71 are arranged separately at the bottom of the Periodic Table. This series of elements is called lanthanides.
  • Similarly, elements with proton numbers 89 to 103 in Period 7 are arranged separately at the bottom of the Periodic Table. This series of elements is called actinides.

Metallic and non-metallic properties

  • Element in Group 1, 2 and 13 are metals.
  • Transition elements in Group 3 to 12 are also metals.
  • Elements in Group 15, 16, 17 and 18 are non-metals.
  • In Group 14,
    • Carbon and silicon are non-metals.
    • Germanium is a metalloid (semimetal)
    • Tin and lead are metals.

1. Relationship between the electron arrangement and the position of the element in the Periodic Table

Figure shows the electron arrangements of the elements with proton numbers 1 to 20 in the Periodic Table.

2. Relationship between the electron arrangement and the group number of an element

  • Based on above Figure, the group number of an element is determined by the number of valence electrons in an atom of the element.
  • Table shows the relationship between the number of valence electrons and the group number of an element.
    Periodic-Table-3
  • For elements with 1 or 2 valence electrons,
    Group number of that element = Number of valence electrons
  • For elements with 3 to 8 valence electrons,
    Group number of that element = Number of valence electrons plus 10
    Note:
    Helium with an electron arrangement of 2 is placed in Group 18. This is an exception.
    This is because helium has similar inert properties as the other noble gases in Group 18.

Example: Element Q has a nucleon number of 27. An atom of element Q contains 14 neutrons. In which group is element Q located in the Periodic Table?
Solution:
Number of electrons in an atom Q = Number of protons
= 27 – 14 = 13
Electron arrangement of atom Q = 2.8.3
Number of valence electrons = 3
∴ Group number = 3 + 10 = 13
Hence, element Q is located in Group 13 of the Periodic Table.

3. Relationship between the electron arrangement and the period number of an element

  • Based on above Figure, the period number of an element is determined by the number of shells occupied with electrons in an atom of that element.
  • Table shows the relationship between the number of shells occupied with electrons and the period number of an element.
    Periodic-Table-4
  • Hence,
    Period number of an element = Number of shells occupied with electrons in an atom of that element

Example: Element T has a proton number of 19 and a nucleon number of 39. In which period is element T located in the Periodic Table?
Solution:
Number of electrons in atom T
= Number of protons in atom T
= Proton number =19
∴ Electron arrangement of atom T = 2.8.8.1
Atom T has 4 shells occupied with electrons. Hence, element T is located in Period 4 of the Periodic Table.

Example: Element R is located in Group 15 and Period 3 of the Periodic Table. What is the electron arrangement of an atom of element R?
Solution:
Atom R has 5 valence electrons because it is in Group 15.
Atom R has 3 shells occupied with electrons because it is in Period 3.
Electron arrangement of atom R = 2.8.5

4. Elements with the same number of valence electrons will exhibit similar chemical properties.
For example:
Atom W with an electron arrangement of 2.8.2 and atom X with an electron arrangement of 2.8.8.2 exhibit similar chemical properties.
This is because both the atoms of W and X have 2 valence electrons, that is the same number of valence electrons.

Periodic Table Mnemonics

Mnemonics are easy-to-remember lines or phrases one can use to memorize things that are difficult to learn. In this article, you will find Hindi mnemonics – one each for one group – to learn the Periodic Table

The Periodic Table provides the names, atomic numbers, symbols and atomic weights of known elements. It serves as a great tool for solving chemistry problems.

A periodic table is divided into groups (columns), where elements with each group behave similarly while bonding with other elements; and periods (rows), where elements in one period have same number of electron shells.

Here are some fun, interesting and naughty mnemonics in Hindi used by the backbenchers to memorize elements along each group or period:

Key To Reading These Mnemonics Or Hindi Sentence:

• These sentences contain letters denoting symbols of elements in the same order as they occur in a group or period.
• The symbols have been highlighted as bold letters in the sentence. However at the places where the complete symbol could not be included in the sentence, the first letters have been strung together and the second letter is shown in brackets. While reading the sentence you don’t have to read the letters in bracket. Just keep them in mind.
• At some places, phonetics have been used to denote a symbols such as ‘c’ could be replaced by ‘k’,’g’ with ‘j’, ‘I’ with ‘ea’ and ‘o’ with ‘u’, to make the sentence easier to remember.

S-Block Elements

Consisting of the first two groups, S-block elements have quite similar physical and chemical properties. The valence electrons of the elements in this block occupy s-orbitals.

Group 1 is known as alkali metals. It includes Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Ru), Caesium (Cs), and Francium (Fr).

Mnemonic for Group 1: LiNa Ki Ruby Cse Friendship hai.

Group 2 is known as alkaline earth metals. It includes Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Br), and Radium (Ra).

Mnemonic for Group 2: Beta Mange Car Scooter Baap rone se Raazi

P-Block Elements

Consisting of last six groups of the periodic table (Groups 13 to 18), P-block elements have their valence electrons occupying p-orbitals.  This block consists of non-metals, semi-metals and poor metals.

Group 13 is known as Boron group or the group of Icosagens or Triels. It includes Boron (B), Aluminium (Al), Gallium (Ga), Indium (In), and Thallium (Tl).

Mnemonic for Group 13: B A G I T.

Group 14 is known as Carbon group or the group of Crystallogens, Tetragens or Tetrels. It includes Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), and Lead (Pb).

Mnemonic for Group 14: Chemistry Sir Gives Sanki Problems.

Group 15 is known as the group of Pnictogens or Nitrogen group. It includes Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb), and Bismuth (Bi).

Mnemonic for Group 15: Nahi Pasand Aise Sab Bhai.

Group 16 is known as the group of Chalcogens or Oxygen group. It includes Oxygen (O), Sulphur (S), Selenium (Se), Tellurium (Te), and the radioactive element Polonium (Po).

Mnemonic for Group 16: Oh! Style Se Tel Polish.

Group 17 is known as the group of Halogens. It includes Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At).

Mnemonic for Group 17: Fir Call kar Bahaar AayI Aunty.

Group 18 is known as the group of Noble gases, excluding Helium. Normally, they are all odorless and colorless gases with very low chemical reactivity. The group includes Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and the radioactive Radon (Rn).

Mnemonic for Group 18: He Never Arrived; Kara Xero Run pe out.

D-Block Elements

D-Block elements consist of element groups 3 to 12 that correspond to the filling of the d-orbital subshell of the second outermost shell. Groups 3 to 11 are also known as transitional metals. Group 12 elements, which have its d subshell completely filled, are also known as post-transition elements.

D-block elements and F-block elements show considerable similarities across the periods too.

We can memorize these elements across the periods:

Period 4 elements are quite stable and many of them are very common in earth’s crust or core or both. D-block elements it includes are Scandium (Sc), Titanium (Ti), Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu) and Zinc (Zn).

Mnemonic for Period 4: Science Ti(ea)cher Vineeta Criplani Man Fenko (FeCo) Ni Kyun(Cu) Zaan hai?

Read as: Science Teacher Vineeta Kriplani manfenko ni kyun zaan hai?

Period 5 elements are known to fill their 5s shell first, then 4d shells and then 5p shells, with rhodium being the exception. The elements of this period show many exceptions to Maledung rule. D-block elements it includes are Yttrium (Y), Zirconium (Zr), Niobium (Nb), Molybdenum (Mo), Technetium (Tc), Ruthenium (Ru), Rhodium (Rh), Pd (Palladium), Silver (Ag) and Cadmium (Cd).

Mnemonic for Period 5: Yeh Zarra Nabi bana Mohabaat mein T(c)eri, R(u)o R(h)o P(d)ukarogi Aaj(g) ise Chandni

Read as: Yeh Zarra Nabi bana Mohabbat mein Teri, Ro Ro Pukarogi Aaj ise Chandni

Period 6 includes the lanthanides or rare earths. Some of these transition metals are very valuable such as gold. D-block elements it includes are Lutetium (Lu), Hafnium (Hf), Tantalum (Ta), Tungsten (W), Rhenium (Re), Osmium (Os), Iridium (Ir), Platinum (Pt), Gold (Au) and Mercury (Hg).

Mnemonic for Period 6: L(u)a HafTa Warna Reh Us(Os) Irritating Popat ke saath Aur Hoj(g)a pagal.

Read as: La Hafta Warna Reh Us Irritating Popat ke saath Aur Hoja pagal.

Period 7 contains the radioactive elements only. It includes actinides which include the heaviest naturally occurring element Californium. All other elements are synthesized artificially. D-block elements

it includes are Actinium (Ac), Rutherfordium (Rf), Dubnium (Db), Seaborgium (Sg), Bohrium (Bh), Hassium (Hs), Meitnerium (Mt), and Darmstadtium (Ds).

Mnemonic for Period 7: Ak(c)ele R(f) D(b) S(g)harma ki B(h)ook mein H(s)ain Maths ke Difficult sawaal.
Read as: Akele R D Sharma ki Book mein Hain Maths ke Difficult sawaal.

F-Block Elements

F-block elements have their valence electrons in f-orbitals. They are also known as inner transition elements. They can be divided into Lanthanides (also known as rare earth elements) and Actinides that are highly reactive to halogens and chalcogens like lanthanides but they react more easily.

Lanthanides include Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), Holmium (Ho), Erbium (Er), Thulium (Tm), Ytterbium (Yb) and Lutetium (Lu).

We can learn all these in three parts:

  1. Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), and Samarium (Sm)

Mnemonic for Lanthanides Part 1: Celina aur Priety Ne dande se Pammy aur Simmy ko mara.

  1. Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), and Holmium (Ho)

Mnemonic for Lanthanides Part 2: Europe G(d)aya to TB(b) aur Di(y)arrohoea Ho gaya.

Read as: Europe Gaya to TB aur Diarrohoea Ho gaya.

  1. Erbium (Er), Thulium (Tm), Ytterbium (Yb) and Lutetium (Lu)

Mnemonic for Lanthanides Part 3: E re, dekh Tamatar Yellow aur bLue hain.

Actinides include these f-block elements – Thorium (Th), Protactinium (Pa), Uranium (U), Neptunium (Np), Plutonium (Pu), Americium (Am), Curium (Cm), Berkelium (Bk), Fermium (Fm), Mendelevium (Md), Nobelium (No), and Lawrencium (Lr).

We can learn all these in three parts too:

1.Thorium (Th), Protactinium (Pa), Uranium (U), and Neptunium (Np)

Mnemonic for Actinides Part 1: Thode Pehelwan Unse Niptengey.

2.Plutonium (Pu), Americium (Am), Curium (Cm), Berkelium (Bk)

Mnemonic for Actinides Part 2: Purane Aam K(C)am Bikenge.

Read as: Purane Aam Kam Bikenge.

  1. Fermium (Fm), Mendelevium (Md), Nobelium (No), and Lawrencium (Lr)
    Mnemonic for Actinides Part 3: ItniFamily aMdani mein No Ladki rajee.