Description : Explain the significance of spin quantum number.
Last Answer : Ans.The direction of spinning of an electron in an orbit as well as the net magnetic moment of an orbital.
Description : Explain the significance of Azimuthal quantum number.
Last Answer : Ans. It refers as sub-energy level of an atom.
Description : How many quantum numbers are needed to designate an orbital?
Last Answer : Ans.Three quantum numbers.
Description : What are different types of quantum numbers , write them with their symbols ?
Last Answer : Ans. 1.Principal Quantum Numbers (n) 2.Azimuthal Quantum Numbers(l) 3.Magnetic Quantum Numbers (m) 4.Spin Quantum Numbers(s)
Description : What is the difference between Quantum and photon?
Last Answer : Ans. The smallest packet of Energy of any radiation is called as Quantum and that of Light is known as Photon.
Description : What is Aufbau’s principle? How it helps to fill electrons in an atom in different orbitals?
Last Answer : Ans Electrons are filled in orbitals of an atom according to increasing energies which is in accordance to (n+l) values of electrons. If (n+l )values are same the electron goes to orbital having lower value of n.
Description : Two electrons in an orbital are differentiated by which of the following? (1) Magnetic quantum number (2) Spin quantum number (3) Principal quantum number (4) Azimuthal quantum number
Last Answer : (2) Spin quantum number Explanation: Spin quantum number is the is the fourth quantum number that differentiates two electrons in the same orbital. The Pauli exclusion principle states that "no two ... atom. Each electron must have a different spin or occupy a different shell from any other.
Description : Two electrons in an orbital are differentiated by which of the following ? (1) Magnetic quantum number (2) Spin quantum number (3) Principal quantum number (4) Azimuthal quantum number
Last Answer : Spin quantum number
Description : What is Hund’s rule of maximum multiplicity? What is its significance?
Last Answer : Ans Pairing of electrons in an orbital takes place only when all orbitals of same sub-shell become singly occupied. It helps to equalize energy of a sub-shell
Last Answer : (2) Spin quantum number Explanation: Spin quantum number is the fourth quantum number that differentiates two electrons in the same orbital.
Description : Tell what would happen to the stability of an atom, with atomic number higher than18, if the aufbau principle was not introduced.
Last Answer : Ans. We cannot find out the exact reason of stability of an atom & why they should have filled inner orbits before outermost shell.
Description : Find the number of radial and angular nodes in 3d subshell?
Last Answer : Ans. Zero-angular node as well as radial nodes.
Description : What do you mean by Pauli’e exclusive principle? What is its significance?
Last Answer : Ans No two electrons will have same set of all q.no. If n,l,m are same i.e. same orbital ‘s’ will be differ. It shows that all electrons have a definite place in an atom or their own identity.
Description : Explain why half-filled orbitals have extra stability.
Last Answer : Ans. It has symmetrical electron density as well as greater exchange energy.
Description : How many of the following are possible: 1p, 2s, 3p, 3f, 3d.
Last Answer : Ans.2s , 3p & 3d are possible.
Description : What accounts for the stability of an electron in multi-electron atom?
Last Answer : Ans. i.The angular momentum of an electron is integral multiple of h/2ח ii. The symmetrical electron density of an orbit. iii.The maximum transition energy of an orbital.
Description : Is the energy of an electron in 2s orbital same as of that in 2p orbital? Why?
Last Answer : Ans. No, the energy depends upon (n+l) values in an atom. Hence 2p orbital has greater energy than 2s.
Description : “In reality all the s-orbitals are spherically symmetric.” What does this represent?
Last Answer : Ans. The probable density of an electron in s-orbital is equally distributed at all coordinates in space.
Description : Why is s-orbital orbital considered non directional while p-orbital directional?
Last Answer : Ans. Electron density in s-orbital is equal in all direction while it dumble shaped along one axis in p- orbitals.
Description : Define Pauli’s exclusion principle ?
Last Answer : Ans. No two electrons in an atom can have same set ofall four quantum numbers. If three are same one Quantum number must have different value.
Description : Give the points of Rutherford Model.
Last Answer : Ans. 1. Atom is neutral. 2.Whole mass is concentrated in nucleus. 3.Electrons are revolving in orbits.
Description : Write two properties which cannot be explain by wave nature of radiation
Last Answer : Ans. 1.Photo electric effect 2. Black Body radiation
Description : Write the draw back of Rutherford Atomic Model.
Last Answer : Ans (1). He was unable to explain the stability of Atom. (2). He could not explain the line spectrum.
Description : Why; e/m value is not constant for canal rays ?
Last Answer : Ans. Mass of particles of cathode rays is not constant.
Description : What is threshold frequency?
Last Answer : Ans –The minimum frequency required to eject out electron from an atom.
Description : Name the spectral series which appear in the region of electromagnetic spectrum. (a) Visible region (b) UV region (c) Far IR region
Last Answer : Ans: (a) Balmer Series (b) Lymen Series (c) Pfund Series
Description : State Heisenberg Uncertainty Principle.
Last Answer : Ans. It is impossible to determine the exact position & exact momentum or velocity of microscopic particle.
Description : The orbital angular momemtum quantum number indicates which one of the following? w) the average distance of the electrons from the nucleus x) the direction of spin of the electron y) the shape of the orbital z) the position about the three axes in space of the orbital
Last Answer : ANSWER: Y -- THE SHAPE OF THE ORBITAL
Description : The orientation of an atomic orbital is governed by – (1) principal quantum number (2) magnetic quantum number (3) spin quantum number (4) azimuthal quantum number
Last Answer : (2) magnetic quantum number Explanation: Quantum numbers may be defined as a set of four numbers which give complete information about the electron in an atom, i.e., energy, orbital occupied, size ... tells the number of orientations which the orbitals present within the same sub-shell can take up.
Description : The orientation of an atomic orbital is governed by (1) principal quantum number (2) magnetic quantum number (3) spin quantum number (4) azimuthal quantum number
Last Answer : magnetic quantum number
Description : Five valence electrons of `.^(15)P` re labelled as If the spin quantum numbers of B and Z is `+(1)/(2)`, the group of electron with three of the quant
Last Answer : Five valence electrons of `.^(15)P` re labelled as If the spin quantum numbers of B and Z is `+(1)/(2)`, ... A. AB,XYZ,BY B. AB C. XYZ,AZ D. AB,XYZ
Description : Which of the following indicates the shape of the orbital in which the electron moves? w) principal quantum number x) spin quantum number y) angular momentum quantum number z) none of these
Last Answer : ANSWER: Y -- ANGULAR MOMENTUM QUANTUM NUMBER
Description : The azimuthal quantum number determines the: w) spin of an electron x) shape of an orbital y) size of an orbital z) energy of an orbital
Last Answer : ANSWER: X -- SHAPE OF AN ORBITAL
Description : (2) Exclusion Principle of Pauli Explanation: The Pauli exclusion principle is the quantum mechanical principle that no two identical fermions (particles with half-integer spin) may occupy the same ... function for two identical fermions is anti-symmetric with respect to exchange of the particles.
Last Answer : The three elements most needed in common fertilizers are – (1) Sulphur, Phosphorous and Sodium (2) Nitrogen, Phosphorous and Sodium (3) Phosphorous, Sodium and Nitrogen (4) Calcium, Phosphorous and Potassium
Description : How many 3s electrons are in Mg?
Last Answer : Magnesium atoms have 12 electrons and the shell structure is 2.8. 2. The ground state electron configuration of ground state gaseous neutral magnesium is [Ne]. 3s2 and the term symbol is 1S0.
Description : What is the maximum number of electrons in an atom that can have the quantum number n = 3 and l = 2 ?
Last Answer : What is the maximum number of electrons in an atom that can have the quantum number n = 3 and l = 2 ? A. 2 B. 5 C. 6 D. 10
Description : When there are two electrons in the same orbital, they have: (1) same spin (2) opposite spin (3) same or opposite spin (4) no spin
Last Answer : opposite spin
Description : The number of waves made by an elec- tron moving in an orbit having maximum magnetic quantum number is +3?
Last Answer : 4
Description : “All the four quantum numbers of two electrons in an atom are not the same.” It is the law of — (1) Hund’s (2) Exclusion Principle of Pauli (3) Uncertainty Principle of Hiesenberg (4) Avogadro’s Law
Last Answer : Exclusion Principle of Pauli
Description : The following gas phase reactions are carried out isothermally in a CSTR. A → 2R ; r1 = k1pA ; k1 = 20mole/(sec.m3 bar) A → 3S ; r2 = k2 pA ; k2 = 40mole/(sec.m3 .bar) What is the maximum possible value of FR(mole/sec.)? (A) 1/3 (B) 1/2 (C) 2/3 (D) 2
Last Answer : (C) 2/3
Description : A triangular section having base b, height h, is placed with its base horizontal. If the shear stress at a depth y from top is q, the maximum shear stress is (A) 3S/bh (B) 4S/bh (C) 4b/Sh (D) 3b/bS
Last Answer : (A) 3S/bh
Description : The number of unpaired electrons in `d^(6)`, low spin, octahedral complex is :
Last Answer : The number of unpaired electrons in `d^(6)`, low spin, octahedral complex is : A. 4 B. 2 C. 1 D. 0
Description : In argon, find the numer of electrons with spin value `+(1)/(2)`
Last Answer : In argon, find the numer of electrons with spin value `+(1)/(2)`
Description : The electrons which spins about its axis will possess what kind of energy? A. Translational energy B. Spin energy C. Rotational kinetic energy D. Sensible energy
Last Answer : Spin energy
Description : The electrons in an atom which rotate about the nucleus possess what kind of energy? A. Translational energy B. Spin energy C. Rotational kinetic energy D. Sensible energy
Last Answer : Rotational kinetic energy
Description : Which one of the following statements is WRONG? (A) A singlet or triplet state may result when one of the electrons from the HOMO is excited to higher energy levels (B) In an ... the electron from the singlet excited state returns to ground state, the molecule always shows fluorescence phenomenon
Last Answer : (C) Triplet excited state is more stable than the singlet excited state
Description : What information does the second quantum number of an electrons give?
Last Answer : The type of orbital the electron is in.
Description : An orbital for which n=3 and l = 1 (read: ell equa 1) is called a: w) 2d orbital x) 3d orbital y) 3s orbital z) 3p orbital
Last Answer : ANSWER: Z -- 3p ORBITAL
Description : The correct order of spin-only magnetic moments among the following is : (Atomic number : Mn=25,Co=27,Ni=28,Zn=30)
Last Answer : The correct order of spin-only magnetic moments among the following is : (Atomic number : Mn=25,Co=27,Ni=28,Zn=30) ... (4)]^(2-) gt [ZnCl_(4)]^(2-)`
Description : The spin-only magnetic moment [in units of Bohr magneton, `(mu_(B)` of `Ni^(2+))` in aqueous solution would be (atomic number of `Ni=28)`
Last Answer : The spin-only magnetic moment [in units of Bohr magneton, `(mu_(B)` of `Ni^(2+))` in aqueous solution would be ( ... ` A. 2.84 B. 4.8 C. 0 D. 1.73