Atomic Structure Questions and Answers

1 In a hydrogen atom if energy of an electron in ground state is 13 6 eV then that in the 2nd excited state is AIEEE 2002 a 1 51 eV c 6 04 eV b 3 4 eV d 13 6 eV

3 AsF5 trigonal bipyramidal 4 H O bent 109 Which of the following conversions involves change in both shape and hybridisation 1 BF3 BF4 2 H O H O 3 CH4 C H6 JEE MAINS Onlin 4 NH NH

D 1 shaped Statement 1 p Hydroxybenzoic Statement 2 o Hydroxybenzoic acid has a lower boiling point than o hydroxybenzoic acid acid has intramolecular hydrogen bonding A Statement 1 is True Statement 2 is True Statement 2 is a correct explanation for Statement 1 B Statement 1 is True Statement 2 is True Statement 2 is NOT a correct explanation for Statement 1 C Statement 1 is True Statement 2 is False D Statement 1 is False Statement 2 is True

6 The given graph shows the vapour pressure temperature curves for some liquids V P A B D TI Liquids A B C and D respectively are a diethyl ether acetone ethyl alcohol water b acetone ethyl alcohol diethyl ether water c water ethyl alcohol acetone diethyl ether d ethyl alcohol acetone diethyl ether water

In which of the following complexes in the bond order of C O is minimum 1 Mn CO 3 Ti Co 2 Cr CO 4 V Co

5 A proton and deuteron are accelerated by same potential difference and enter in region of uniform electric field in direction perpendicular to it The deflection of proton is 1 Equal to deflection of deuteron 2 More than deflection of deuteron 3 Less than deflection of deuteron 4 May be more or less than deflection of

P 2 3 60 Consider a hydrogen like ionized atom with atomic number Z with a single electron In the emission spectrum of this atom the photon emitted in the n 2 to n 1 transition has energy 74 8 eV higher than the photon emitted in the n 3 to n 2 transition The ionization energy of the hydrogen atom is 13 6 eV The value of Z is JEE Advanced 2018 P 2 3 601

5 AL The group velocity of the de Broglie wave packet associated with a particle moving with velocity v is 1 equal to v 2 less than v 3 greater than v 4 equal to speed of light

Carbon silicon and germanium atoms have four valence electrons each Their valence and conduction bands are separated by energy band gaps represented by Eg c Eg si and Eg Ge respectively Which of the following relationships is true in their case 1 E F 2 E E

18 A subatomic particle of mass 10 ug is in thermal equilibrium with its surrounding at a temperature of 400 K Then the wave length of this particle will be

50 When the electron of a hydrogen like atom jumps from a higher energy level to a lower energy level then 1 Angular momentum of the electron remains constant 2 Kinetic energy of the electron increases 3 Wavelength of de Broglie wave associated with motion of the electron increases 1 4 Potential oporgy increases X

146 Light of uniform intensity impinges perpendicularly on a totally reflecting surface If the area of the surface is halved the radiation force on it will become double a a b half c four times d one fourth

6 Ionization potential of hydrogen atom is 13 6 el Hydrogen atom in ground state is excited by monochromatic light of energy 12 1 eV The spectra lines emitted by hydrogen according to Bohr s theory will be a one c three 2016 b two d four AIIMS

Q 6 Two H atoms in the ground state collide inelastically The maximu amount by which their combined kinetic energy is reduced is d 27 2 eV a 10 20 eV b 20 40 eV c 13 6 eV

A radiation of energy E falls normally on a perfectly reflecting surface The momentum transferred to the surface is C Velocity of light 1 3 2E C E 2 4 2E

If W is atomic weight and N is the atomic number of an element then CPMT 1971 80 89 a Number of e W N b Number of on W N c Number of H W N d Number of on N

A 100 watt bulb emits monochromatic light of wavelength 400 nm Calculate the number of photons emitted per second by the bulb 20 1 a 3 10 0 s c 2 1020 S 1 b 2 x 10 20 1 d 1 x 10 20 S 1

The density of a solution was determined from the mass of a 10 mL sample of the solution on an analytical balance For this experiment each 10 mL sample was dispensed from one of three different 10 00 mL volumetric pipettes A total of twelve measurements were made where four samples were dispensed from each pipet The calculated density values from each pipet are reported below Glassware Pipet 1 Pipet 2 Pipet 3 1 54 g mL 1 46 g mL 1 43 g ml be tabulated values Calculated Density of Solution 1 55 g mL 1 54 g mL 1 55 g mL 1 41 g mL 1 49 g mL 1 44 g ml 1 50 g mL 1 42 g mL 1 53 g mL which of the ninets give s the most precise results

18 The radius of the first Bohr orbit of a hydrogen atom is 0 53 x 108 cm The velocity o the electron in the first Bohr orbit is A 2 188 x 108 cm s 1 C 1 094 x 108 cm s RIGH NIKE A 2 188 x 108 cm s C 1 094 x 108 cm s 1 B 4 376 108 cm s D 2 188 x 10 cm s A 0 53 x 108 cm 1 B D GUGE OK K 4 376 x 108 cm s 1 2 188 x 10 cm s

DIRECTION Fill up the table below Check to determine the type of force that most evident for each substance SUBSTANCE H F HHH H C C C H 1 II HHH 0 H H N H H KBr in H O POLARI NONPOLAR DIPOLE HYDROGEN ION BOND LONDON DISPERSION DIPOLE FORCES FORCES DIPOLE FORCES

Assertion A In F molecule F F bond is weak Reason R Small size of F atom a A and R both are correct and reason R is correct explanation of A b A and R both are correct but reason R is not correct explanation of A

In which of the following arrangements the order is INCORRECT according to the property indicated against it O O O Li Na K Rb Increasing metallic radius I Br F CI Increasing electron gain enthalpy with negative sign B C N 0 AP Mg Na F

Mathematically the uncertainty principle is presented as Axx Ap 27 12 The value of m for d2 orbital is non zero Two electrons occupying the same orbital of an atom are distinguished by spin quantum number Electrons in the 3d orbitals have different spatial distribution consequently their shielding of one another is relatively small

How many spectral lines will be observed in emission spectrum of hydrogen atom of Hy drogen atom is exposed with a monochrom atic light source for which energy of photon is 12 electron volt electron is present in gr ound state

Example 7 11 How many grams of NaOH must be dissolved in one litre of the solution to have a solution of pH 12 Solution pH log H O 12 log H O 12 H3O 1 10 12 mol L 1 We know that OH Kw H O OH Kw H3O 1x 10 14 1x 10 12 1 x 10 mol L 1 Since NaOH is a strong base it is completely ionized NaOH OH 1 x 10 2 mol L 1 Molecular mass of NaOH 40 Amount of NaOH in grams per litre

RS 4 00 Negative Mark s 1 0 The radius of CI ion is 38 larger than that of the F ion but the radius of the Brion is only 6 5 larger than that of the CI ion The relatively small difference in size between CI and Brion is due to the fact that the Br ion contains ten 3 d electrons which fail to shield the nuclear charge effectively o the Br ion contains ten 3 d electrons which shield the nuclear charge effectively o the Br ion contains six 4p electrons which shield the nuclear charge effectively O the Brion contain ten 3 d electrons and six 3 p electrons together they shield the nuclear charge effectively

In the following reaction NO 2e NO Select the incorrect statement Hybridisation of central atom gets changed Formal charge on central atom gets changed O Oxidation state of central atom gets changed O Maximum number of atoms lying in one plane

The ratio of difference between 1st and 2nd Bohr orbits energy to that between 2nd 3rd orbits energy is A B TIN THESE 1 2 1 3 C 27 5 D 5 27

Outside any orbital the probability of finding the electron is zero For single electronic atom or ion the most probable distance of electron in an orbital having no radial node is n a do Z from the nucleus where a is the first Bohr s radius The average distance of electron belonging from the same orbit from the nucleus decreases with increase in the value of angular momentum quantum number for the orbital

In a H like species there are two energy levels A and B above the ground state having principal quantum numbers of n and no respectively A sample of this H like species has all atoms ions in excited levels A or B only and none in any other energy level Energy of level B is greater than that of level A and a total of 15 different lines are emitted from this sample on returning to ground state out of which 6 lines are emitted due to electronic transitions between the levels n and n only Also energy difference between levels n and Eng En 4 53 eV n Calculate minimum wavelength among all transitions 0 4 3RH 9 8RH

The radial wave function for 1s orbit of a single electron species is given by Ti40 Ke 2 where o 2Zr and K is constant ao radius of Ist Bohr orbit in H atom 1 52 9 pm n is principal quantum number Calculate most probable dis tance of 1 s electron in Be ion Give answer in the form of most probable distance in pm

Sodium emits yellow light with a frequency of 5 09x10 4 Hz when electrons transition from 3p to 3s orbitals I Calculate the energy difference in J between these two orbitals using sections 1 and 2 of the data the booklet

Spider Man No Way Home 3D Hindi Hindi UA Hindi 3D 09 30 AM 12 45 PM 03 05 PM 10 55 P Spider Man No Way Home Hindi Hindi UA Hindi 2D

An unielectronic ion of element A atomic number of element A is n has velocity of electron in xth orbit equal to velocity of electron in H atom in nth orbit Group number of element A in modern periodic is if kinetic energy of electron in H atom in xth orbit is more than 0 2125 eV atom and x n 60houl 3 101

th An unielectronic ion of element A atomic number of element A is n has velocity of electron in x orbit equal to velocity of electron in H atom in nth orbit Group number of element A in modern periodic is if kinetic energy of electron in H atom in xth orbit is more than 0 2125 eV atom and x n Bathoun

59 Which of the following is correct for num electrons number of orbitals and type of c respectively in N orbit 1 4 4 and 8 3 32 16 and 4 2 4 8 and 16 4 4 16 and 32 not of four quon

If n and I are respectively the principle and azimuthal quantum numbers then expression fo calculating total number of electrons in any energ level is 1 n 1 2 21 1 I 1 I n 1 3 2 21 1 1 0 I n 1 2 2 21 1 I 1 I n 1 4 2 21 1 1 0 total number of electron in an energy level orbit nikalne ka formula toh 2n hota hai so why in all options they have given formula of no of electrons in a sub energy level

1 n 1 2 21 1 1 1 I n 1 9 1 n 1 2 2 21 1 1 1 I n 1

Incorrect among the following is are a Number of electrons having m 0 in Na are 7 b Energy of 4s orbital is more than 3d in H atom c Energy of 2s orbital in O is more than carbon 1 a only 2 b only 3 a b only 4 c only

3 pts For a pair of certain electron donor and acceptor pair A G 1 065x10 J Which scenario would you predict would have the fastest electron transfer A Distance is 20 angstroms reorganization energy is 5 065x10 19 J B Distance is 20 angstroms reorganization energy is 1 065x10 19 J C Distance is 60 angstroms reorganization energy is 5 065x10 19 J D Distance is 60 angstroms reorganization energy is 1 065x10 19 J 1

s For a pair of certain electron donor and acceptor pair A G 1 065x10 19 J Which scenario would you predict would have the fastest electron transfer A Distance is 20 angstroms reorganization energy is 5 065x10 19 J B Distance is 20 angstroms reorganization energy is 1 065x10 9 J C Distance is 60 angstroms reorganization energy is 5 065x10 19 J D Distance is 60 angstroms reorganization energy is 1 065x10 19 1

Following are the advantages of double beam instrumentation EXCEPT A Compensate for all but most short term fluctuations in the radiant output of the sou as well as for drift in the transducer and amplifier B Suited for quantitative absorption measurements at a single wavelength C Compensate for wide variations in source intensity with A D Continuous recording of transmittance or absorbance spectra

A mass spectrum is the plot of O O O O 1 point relative abundance of ions against percentage of ions percentage intensity of ions against their mass charge ratio relative abundance of ions against their mass charge ratio relative abundance of ions against number of atoms present

5 i The wavelength of the first line of Lyman series of hydrogen atom is 1215 Calculate the wavelength of the second line of the series and the series limit 6 ii A bike rider approaching a vertical wall observes that the frequency of his bike

3 Which one of the following arrangements represents the correct order of least negative to most negative electron gain enthalpy for C Ca Al F and O a Al Ca 0 C F b Al O C Ca F c C F O Al Ca d Ca Al C O F Karnataka NEET 2013

In the Example of resonating structures of N20 cannot we simply rule out the other two since they do not obey the r ule which states that negative charge should be on electro negative element and positive charge on electropositive el ement

An unknown particle with a mass of 9 10x10 28 grams has wavelength of 9 5 um Use this info to calculate the velocity of the unknown particle in m s Report your answer to 2 or 3 sig figs Do not include units

Q A chemical compound exists in two forms one of which in is found in 10 more than double of other Their respective weights are 220 5 and 225 6 Calculate the average atomic mass of the compound Show proper calculation

The energy of a radiation of wavelength 8000 A is E and energy of a radiation of wavelength 16000 is E What is the relation between thes two 1 E 6 E 3 E E 2 E 2 E 4 E 2 E 22

4 1 and 3 are correct 4 54 A hydrocarbon C5H 0 does not react with chlorine in dark 54 Uch Sich C5H 0 3 but gives a single monochoro compound C H Cl in bright sunlight Identify the hydrocarbon 1 2 H C CH CH CH CH 3 CH CH CH CH CH3 4 None of these 55 Select correct statement s 1 SN reactions of 55 CH Cl for 0 F S R H 2 H C CH CH2 CH2 CH3 3 CH CH CH CH CH 4 chifora ediri atas F R A