2439 + Interview Questions in ATOMIC-STRUCTURE IN GENERAL AWARENESS Page 36 InterviewSolution

1751.	Compare the energy released during direct electronic transition from 4th orbit to lst orbit with the energy released during successive electronic transi tions between the same orbits in H-atom. Is the energy of all successive transitions between the 4th orbit and 1st orbit equal
Answer» expression fbr energy of electron in nth orbit

Discussion

1752.	what is the electronic configuration of `Cu^(2+)` (Z=29) of least positionA. `[Ar]4s^1 3d^8`B. `[Ar]4s^2 3d^10 4p^1`C. `[Ar] 4s^1 3d^10`D. `[Ar] 3d^9`
Answer» Correct Answer - D `._29Cu=[Ar]3d^10 4s^1 , Cu^(2+)=[Ar] 3d^9 . 4s^0` Ground state of `Cu^29=1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^1` `Cu^(2+)=1s^2 , 2s^2 2p^6 , 3s^2 3p^6 3d^9`

Discussion

1753.	`Cu^(2+)` will have the following electronic configuration.A. `1 s^2, 2 s^2 2p^6, 3 s^2 3 p^6 3 d^10`B. `1 s^2, 2 s^2 2p^6, 3 s^2 3 p^6 3 d^9, 4 s^1`C. `1 s^2, 2 s^2 2 p^6, 3 s^2 3p^6 3 d^9`D. `1 s^2, 2 s^2 2 p^6, 3 s^2 3 p^6 3 d^10, 4 s^1`
Answer» Correct Answer - C ( c) Ground state of `Cu^29 = 1 s^2 2 s^2 2 p^6 3 s^2 3p^6 3 s^10 4 s^1` `Cu^(2+) = 1 s^2 2 s^2 2p^6 3 s^2 3 p^6 3 d^9`.

Discussion

1754.	The wave number of the `H_(a)-`line in Balmer series of hydrogen spectrum isA. `5R//36`B. `3R//16`C. `21R//100`D. `3R//4`
Answer» Correct Answer - A `bar(v) = (1)/(lambda) = R [(1)/(n_(1)^(2))-(1)/(n_(2)^(2))]`

Discussion

1755.	What is the electronic configuration of `Cu^(+)` ion
Answer» `1s^(2)2s^(2)2p^(6)3s^(2)3p^(6)4s^(0)3d^(10)`

Discussion

1756.	Light from a discharge tube containing H-atoms in some excited state, falls on the metallic surface of metal Na.The KE of the fastest photo-electron was found to be fastest photo-electron was found to be `10.93eV`. If `He^(+)` ions were present in the same excited state, the KE of the fastest photo-electron would have been `49.18eV`. Determine the excited state orbit number and work function of Na.A. `2,18.2ev`B. `4,1.82ev`C. `3,16ev`D. `2,1.6ev`
Answer» Correct Answer - B `E_(1) = E_(0) +10.93, E_(2) = E_(0) +49.18` `[13.6 xx 2^(2) - 13.6 xx 1^(2)] [(1)/(1^(2))-(1)/(n^(2))]` `= E_(2) - E_(1) = Delta E = 38.25` `:. n = 4, :. E_(1) = 12.75 & E_(0) = 1.82 eV`

Discussion

1757.	In hydrogen atom, energy of first excited state is `- 3.4 eV`. Then, `KE` of the same orbit of hydrogen atom is.A. ` + 3.4 eV`B. `+ 6.8 eV`C. `-13.6 eV`D. `+ 13.6 eV`
Answer» Correct Answer - A (a) `because` Total energy `(E_n) = KE + PE` In the first excited state =`(1)/(2) mv^2 + [-(Ze^2)/( r)]` =`+ (1)/(2) (Ze^2)/( r) - (Ze^2)/( r)` `- 3.4 e V = - (1)/(2) (Ze^2)/( r)` `:. KE = (1)/(2) (Ze^2)/(2) = + 3.4 eV`.

Discussion

1758.	A plot of the kinetic energy `((1)/(2)mv^(2))` of ejected electrons as a function of the frequency (v) of incident radiation for four alkali metals `(M_(1),M_(2),M_(3),M_(4))` is given below: The alkali metals `M_(1),M_(2),M_(3),M_(4)` are respectively:A. Li,Na,K and RbB. Rb,K,Na and LiC. Na, K, Li and RbD. Rb, Li, Na and K
Answer» Correct Answer - B Intercept on v-axis denotes `v_(0)` `v_(0)=(phi)/(h)` where `phi`=work function of the metal. Thus, greater is the value of `v_(0)`, more will be the work function of the metal.

Discussion

1759.	If first ionisation potential of a hypothetical atom is `16 V`, then the first excitation potential will be :A. 10.2 VB. 12 VC. 14 VD. 16 V
Answer» Correct Answer - B (b) `IP = 13.6 Z^2 = 16` (given) First excitation potential `= 13.6 xx (3)/(4) xx Z^2` =`16 xx (3)/(4) = 12 V`.

Discussion

1760.	The first excitation potential of a given atom is `10.2V`,then the ionisation potential isA. `10.2V`B. `13.6V`C. `30.6V`D. `20.4V`
Answer» Correct Answer - B

Discussion

1761.	The correct order of wavelength of Hydrogen `(._(1)H^(1))`, Deuterium `(._(1)H^(2))` and Tritium `(._(1)H^(3))` moving with same kinetic energy isA. `lambda_(H) gt lambda_(D) gt lambda_(r)`B. `lambda_(H)=lambda_(D)=lambda_(r)`C. `lambda_(H) lt lambda_(D) lt lambda_(r)`D. `lambda_(H) lt lambda_(D) gt lambda_(r)`
Answer» Correct Answer - 1

Discussion

1762.	Electronic configuration of deuterium atom isA. `1s^1`B. `2s^2`C. `2s^1`D. `1s^2`
Answer» Correct Answer - A Atomic number of deuterium =1 , `._1D^2 to 1s^1`

Discussion

1763.	Which of the following options is not correct regarding the order of the frequency of electromagnetic radiation?A. Radio waves `lt` Microwaves `lt` X-raysB. Green light `lt` UV light `lt gamma`- radiationsC. Far infrared `gt` Radio waves `gt` Cosmic raysD. Microwaves `lt` Near infrared rays `lt` UV rays
Answer» Correct Answer - C

Discussion

1764.	Which of the following statements is not correct regarding electromagnetic spectrum?A. The velocity of X-rays is more than that of microwavesB. Infra-red radiations have larger wavelength than cosmic raysC. The frequency of microwaves is less than that of ultra-violet raysD. X-rays have larger wave number the micro waves
Answer» Correct Answer - A All types of electromagnetic radiations have same velocity

Discussion

1765.	The energy of photon is inversely proportional to itsA. WavelengthB. FrequencyC. WavenumberD. valency
Answer» Correct Answer - A `E = hv = (hc)/(lambda), E prop (1)/(lambda)`

Discussion

1766.	Many elements have non-integral atomic masses becauseA. they have isotopesB. their isotopes have non-integral massesC. their isotopes have different massesD. the cosstituents, neutrons, protons and electron combine to give fractional masses
Answer» Correct Answer - A::C At. Wt `=(P_(1)M_(1)+P_(2)M_(2)+...)/(p_(1)+p_(2)+...)`

Discussion

1767.	Which statement about cathode rays is/are correct?A. They travel in straight lines towards cathodeB. They produce fluorescent discharge through the walls of the tubeC. They produce heating effectD. They can affect photographic plate
Answer» Correct Answer - B::C::D Cathode rays properties

Discussion

1768.	Electromagnetic radiation with maximum wavelengths is :A. ultravioletB. radio waveC. X-rayD. infrared
Answer» Correct Answer - B

Discussion

1769.	The radiation with highest wave numberA. Micro wavesB. X-raysC. I.R. RadiationsD. Radiowaves
Answer» Correct Answer - B \|X-rays\|U.V rays\|I.R.\|Ratio `rarr lambda uarr`

Discussion

1770.	No. of visible lines when an electron returns from `5^(th)` orbit up to ground state in `H`spectrum :A. 5B. 4C. 3D. 10
Answer» Correct Answer - C ( c) Visible lines `rArr` Balmer series `(5 rarr 2,4 rarr 2,3 rarr 2)`. So `3` lines.

Discussion

1771.	Which type of radiation has the highest frequency ?A. InfraredB. MicrowaveC. UltravioletD. X-rays
Answer» Correct Answer - D

Discussion

1772.	Quantum numbers l=2 and m=0 represent which orbital?A. `d_(xy)`B. `d_(x^(2)-y^(2))`C. `d_(z^(2))`D. `d_(zx)`
Answer» Correct Answer - C

Discussion

1773.	In a container a mixture is prepared by mixing of three samples of hydrogen helium ion `(He^(+))` and lithium ion `(Li^(2+)).` In sample , all the hydrogen atoms are in 1st excited state and all the `He^(+)` ions are in third excited state and all the `Li^(2+))` ions are in fifth excited state. Find the total number of spectral lines observed in the emission spectrum of such a sample when the electrons return back to the ground state.
Answer» Correct Answer - 20

Discussion

1774.	A portons is accelrated to one -tenth of the velocity of light . If its velocity can be be measured with a precision `pm 1%`. wavelenght of `1 xx10^(-10)`m.
Answer» Correct Answer - `1.05xx10^(-13)m` `Delta"x".m.Deltage(h)/(4pi)` `Delta"x"ge(h)/(4pi.mDeltaV)=(h)/(4pim((c)/(10))xx((1)/(100)))` so `D"x"ge1.05xx10^(-13)m`

Discussion

1775.	Which statement concerning visible light is correct ?A. The product of wavelength and frequency is a constant for visible light in a vacuum.B. As the wavelength of light increases the energy of a photon increases.C. As the wavelength of light increases its amplitude also increases.D. Green light has a higher frequency than blue light .
Answer» Correct Answer - A

Discussion

1776.	The angular momentum of p electron isA. `sqrt( 2) h`B. `h`C. `sqrt(6) h`D. `2 h`
Answer» Correct Answer - A (a) Orbital angular momentum `L = sqrt(l(l + 1)) ħ` where `ħ = (h)/(2 pi)` :. `L` for `p` electron `= sqrt(1(1 + 1) ħ) = sqrt(2) ħ`.

Discussion

1777.	The work functions for metals ` A, B` and ( C) are presepctively ` 1. 92 eV` , `2, 0` eV 1 and ` 5.0 eV` According to Einstein equation , the metal which will emit photoelectron for a radistion fo wavelingth ` 4100 Å`/areA. A onlyB. (A) and (B) onlyC. A, B and ( C)D. None of these
Answer» Correct Answer - B `E= (12375)/(lambda_(("in "Å))) = (12375)/(4100) = 3.018 eV` Thus only (A) and (B) will eject photo electrons .

Discussion

1778.	Light of wavelength `lambda` falls on metal having work functions `hc//lambda_(0)` . Photoelectric effect will take place only if :A. `lambda ge lambda_(0)`B. `lambda ge 2 lambda_(0)`C. `lambda le lambda_(0)`D. `lambda le lambda_(0)//2`
Answer» Correct Answer - C

Discussion

1779.	The work function for metals X , Y and Z are respectively 1.92 eV , 2.0 eV and 5.0 eV . According to Einstein equation , the metal which will emit photoelectrons for a radiation of wavelength `4100 "Å"` is/ are :A. X onlyB. X and Y onlyC. X , Y and ZD. X and Z
Answer» Correct Answer - B

Discussion

1780.	The positive charge of an atom is.A. spread all over the atomB. distributed around the nucleusC. concentrated at the nucleusD. all of these
Answer» Correct Answer - C ( c) Positive charge of an atom is present in nucleus.

Discussion

1781.	Which of the following best explains light both as a stream of particles and wave motion ?A. DiffractionB. `lamda = h//p`C. InterferenceD. Photoelectric effect.
Answer» Correct Answer - B (b) `lamda = (h)/(p)` or `(h)/(mv)` or `(h)/(mc)` de-Broglie equation.

Discussion

1782.	The uncertainty in position and velocity of the particle are 0.1 nm and `5.27xx10^(-24) ms^(-1)` respectively then find the approximate integral mass of the particle (in g ) . `(h=6.625xx10^(-34) Js)`
Answer» Correct Answer - 100

Discussion

1783.	The uncertainty in position and velocity of the particle are `0.1 nm` and `5.27 xx 10^-27 ms^-1` respectively. Then the mass of the particle is : `(h = 6.625 xx 10^-34 J s)`.A. 200gB. 300 gC. 100 gD. 1000 g
Answer» Correct Answer - C

Discussion

1784.	The uncertainty in position and velocity of the particle are `0.1 nm` and `5.27 xx 10^-27 ms^-1` respectively. Then the mass of the particle is : `(h = 6.625 xx 10^-34 J s)`.A. 200 gB. 300 gC. 100 gD. 1000 g
Answer» Correct Answer - C ( c) `Delta x = 0.1 xx 10^-9 m` `Delta V = 5.27 xx 10^-27 ms^-1` `:. Delta x xx m Delta V = (h)/(4 pi)` :. `0.1 xx 10^-9 xx m xx 5.27 xx 10^-27 = 0.527 xx 10^-34` `:. m = 0.1 kg = 100 g`.

Discussion

1785.	The uncertainty in position and velocity of the particle are `0.2mm` and `10.54xx10^(-27)ms^(-1)` respectively then the mass of the particle is `: ( h=6.625xx10^(-34)Js)`A. `48.86g`B. `30.86g`C. `24.86gm`D. `100g`
Answer» Correct Answer - 3 `Deltax=0.2 xx10^(-9)m`. `DeltaV=10.54xx10^(-27)ms^(-1)` `:. " "Deltax xxmDeltaV=(h)/(4pi)` `:." "0.2xx10^(-3)xxmxx10.54xx10^(-27)=0.527xx10^(-34)` `m=24.86gm`

Discussion

1786.	If wavelength is equal to the distance travelled by the electron in one second thenA. `lambda = h//p`B. `lambda = h//m`C. `lambda = sqrt(h//p)`D. `lambda = sqrt(h//m)`
Answer» Correct Answer - D `lambda = (h)/(mv)` distance travelled in one second by velocity `bar V = vcm = olambda` `lambda = (h)/(m lambda) rArr lambda^(2) = (h)/(m) rArr lambda = sqrt((h)/(m))`

Discussion

1787.	If wavelength is equal to the distance travelled by the electron in one second, thenA. `lambda=(h)/(p)`B. `lambda=(h)/(m)`C. `lambda=sqrt((h)/(p))`D. `lambda=sqrt((h)/(m))`
Answer» Correct Answer - D Acc to schrodinger model `e^(-)` behave as wave only.

Discussion

1788.	If wavelength is equal to the distance travelled by the electron in one second , then :A. `lambda = (h)/(p)`B. `lambda =(h)/(m)`C. `lambda = sqrt((h)/(p))`D. `lambda = sqrt((h)/(m)`
Answer» Correct Answer - D

Discussion

1789.	The mass number of three isotopes of an element are 10,12,14 units. Their percentage aboundance is 80,15 and 5 units respectively. What is the atomic weight of the element?
Answer» Percentage abundances of Isotopes =80,15,5 ratio of percentage abundances of Isotopes =16:3:1 The total ratio `= 16 +3 +1 = 20` avg. Awt `=(sum "ratio of % abundance" xx "Atomic weights")/("Total ratio")` `= (10 xx 16 +12 xx 3 +14 xx 1)/(20) = 10.5` The average Atomic weight `=10.5`

Discussion

1790.	The value of the spin only magnetic moment of a particular ion is 2.83 Bohr magneton. The ion isA. `Fe^(2+)`B. `Ni^(2+)`C. `Mn^(2+)`D. `Co^(3+)`
Answer» Correct Answer - B `mu = sqrt(n(n+2))` Where `n = 2`

Discussion

1791.	Which of the following ion is not isoelectronic with `O^(2-)` ?A. `N^(3-)`B. `F^-`C. `TI^(+)`D. `Na^(+)`
Answer» Correct Answer - C

Discussion

1792.	Calculate the minimum uncertainty in velocity of a particle of mass `1.1 xx 10^-27 kg` if uncertainty in its position is `3 xx 10^-10 cm`.A. `1.5 xx 10^-4 m`B. `2.5 xx 10^-4 m`C. `3.5 xx 10^-4 m`D. `4.5 xx 10^-4 m`
Answer» Correct Answer - A (a) `Delta x, Delta v ge (h)/(4 pi m)` `Delta v ge (h)/(Delta x. 4 pi. M)` =`(6.6 xx 10^-34)/(3 xx 10^-10 xx 10^-2 m xx 4 xx 3.14 xx 1.1 xx 10^-27)` =`1.5 xx 10^-4 m`.

Discussion

1793.	If wavelength is equal to the distance travelled by the electron in one second, thenA. `lamda = (h)/(p)`B. `pi = (h)/(m)`C. `lamda = sqrt((h)/(p))`D. `lamda = sqrt((h)/(m))`
Answer» Correct Answer - D (d) `lamda = v` then `lamda = (h)/(mV)` or `lamda^2 = (h)/(m)` So, `lamda = sqrt((h)/(m))`.

Discussion

1794.	The relative atomic mass of an element A is 16.2 . There are two isotopes `""_(8)^(16)A` and `""_(8)^(18)A` of the element. Calculate the percentage of these two isotopes present in the element .
Answer» `""_(8)^(16)A=90%, ""_(8)^(18)A=10%`

Discussion

1795.	A naturally occuring sample of lithium contains 7.42% of `""^(6)Li` and 92.58% `""^(7)Li`. The relative atomic mass of `""^(6)Li` is 6.015 and that of `""^(7)Li` is 7.016. Calculate the atomic mass of a naturally occuring sample of lithium.
Answer» Atomic mass `=((6.015xx7.42)(7.016xx92.58))/(100)=6.94`

Discussion

1796.	The hydride ions `(H^-)` are isoelectronic withA. `L i`B. `He^+`C. `He`D. `Be`
Answer» Correct Answer - C ( c) `H^- = 1 s^2 and He = 1 s^2`.

Discussion

1797.	The hydride ion is isoelectronic with Electromagnetic RadiationA. `H^(+)`B. `He^(+)`C. HeD. Be
Answer» Correct Answer - C Hydride ion `(H^(-))` have 2 electrons

Discussion

1798.	Which combinations of quantum number `n,l,m,s` for the electron in an atom does not provide a permission solution of the wave equation ?A. `3,2,-2,1//2`B. `3,3,1,-1//2`C. `3,2,1,1//2`D. `3,1,1,-1//2`
Answer» Correct Answer - B

Discussion

1799.	The ratio of the atomic numbers of two elements A and B is `2:3` A is an intery gas the first 3 orbits completely filled. Identify A and B and write their electronic configurations.
Answer» `Ato` electronic configuration `-2,8,18,8`. Thus, the atomic number `=36`. `A:B=2:3` `therefore B=(36xx3)/(2)=54` The electronic configuration of `B=2,8,18,18,8`

Discussion

1800.	The hydride ions `(H^-)` are isoelectronic withA. LiB. `He^+`C. HeD. Be
Answer» Correct Answer - C `H^- =1s^2` and `He^+ =1s^2`

Discussion

Explore topic-wise InterviewSolutions in .

Compare the energy released during direct electronic transition from 4th orbit to lst orbit with the energy released during successive electronic transi tions between the same orbits in H-atom. Is the energy of all successive transitions between the 4th orbit and 1st orbit equal

what is the electronic configuration of `Cu^(2+)` (Z=29) of least positionA. `[Ar]4s^1 3d^8`B. `[Ar]4s^2 3d^10 4p^1`C. `[Ar] 4s^1 3d^10`D. `[Ar] 3d^9`

`Cu^(2+)` will have the following electronic configuration.A. `1 s^2, 2 s^2 2p^6, 3 s^2 3 p^6 3 d^10`B. `1 s^2, 2 s^2 2p^6, 3 s^2 3 p^6 3 d^9, 4 s^1`C. `1 s^2, 2 s^2 2 p^6, 3 s^2 3p^6 3 d^9`D. `1 s^2, 2 s^2 2 p^6, 3 s^2 3 p^6 3 d^10, 4 s^1`

The wave number of the `H_(a)-`line in Balmer series of hydrogen spectrum isA. `5R//36`B. `3R//16`C. `21R//100`D. `3R//4`

What is the electronic configuration of `Cu^(+)` ion

In hydrogen atom, energy of first excited state is `- 3.4 eV`. Then, `KE` of the same orbit of hydrogen atom is.A. ` + 3.4 eV`B. `+ 6.8 eV`C. `-13.6 eV`D. `+ 13.6 eV`

If first ionisation potential of a hypothetical atom is `16 V`, then the first excitation potential will be :A. 10.2 VB. 12 VC. 14 VD. 16 V

The first excitation potential of a given atom is `10.2V`,then the ionisation potential isA. `10.2V`B. `13.6V`C. `30.6V`D. `20.4V`

Electronic configuration of deuterium atom isA. `1s^1`B. `2s^2`C. `2s^1`D. `1s^2`

The energy of photon is inversely proportional to itsA. WavelengthB. FrequencyC. WavenumberD. valency

Many elements have non-integral atomic masses becauseA. they have isotopesB. their isotopes have non-integral massesC. their isotopes have different massesD. the cosstituents, neutrons, protons and electron combine to give fractional masses

Which statement about cathode rays is/are correct?A. They travel in straight lines towards cathodeB. They produce fluorescent discharge through the walls of the tubeC. They produce heating effectD. They can affect photographic plate

Electromagnetic radiation with maximum wavelengths is :A. ultravioletB. radio waveC. X-rayD. infrared

The radiation with highest wave numberA. Micro wavesB. X-raysC. I.R. RadiationsD. Radiowaves

No. of visible lines when an electron returns from `5^(th)` orbit up to ground state in `H`spectrum :A. 5B. 4C. 3D. 10

Which type of radiation has the highest frequency ?A. InfraredB. MicrowaveC. UltravioletD. X-rays

Quantum numbers l=2 and m=0 represent which orbital?A. `d_(xy)`B. `d_(x^(2)-y^(2))`C. `d_(z^(2))`D. `d_(zx)`

A portons is accelrated to one -tenth of the velocity of light . If its velocity can be be measured with a precision `pm 1%`. wavelenght of `1 xx10^(-10)`m.

The angular momentum of p electron isA. `sqrt( 2) h`B. `h`C. `sqrt(6) h`D. `2 h`

The work functions for metals ` A, B` and ( C) are presepctively ` 1. 92 eV` , `2, 0` eV 1 and ` 5.0 eV` According to Einstein equation , the metal which will emit photoelectron for a radistion fo wavelingth ` 4100 Å`/areA. A onlyB. (A) and (B) onlyC. A, B and ( C)D. None of these

Light of wavelength `lambda` falls on metal having work functions `hc//lambda_(0)` . Photoelectric effect will take place only if :A. `lambda ge lambda_(0)`B. `lambda ge 2 lambda_(0)`C. `lambda le lambda_(0)`D. `lambda le lambda_(0)//2`

The work function for metals X , Y and Z are respectively 1.92 eV , 2.0 eV and 5.0 eV . According to Einstein equation , the metal which will emit photoelectrons for a radiation of wavelength `4100 "Å"` is/ are :A. X onlyB. X and Y onlyC. X , Y and ZD. X and Z

The positive charge of an atom is.A. spread all over the atomB. distributed around the nucleusC. concentrated at the nucleusD. all of these

Which of the following best explains light both as a stream of particles and wave motion ?A. DiffractionB. `lamda = h//p`C. InterferenceD. Photoelectric effect.

The uncertainty in position and velocity of the particle are 0.1 nm and `5.27xx10^(-24) ms^(-1)` respectively then find the approximate integral mass of the particle (in g ) . `(h=6.625xx10^(-34) Js)`

The uncertainty in position and velocity of the particle are `0.1 nm` and `5.27 xx 10^-27 ms^-1` respectively. Then the mass of the particle is : `(h = 6.625 xx 10^-34 J s)`.A. 200gB. 300 gC. 100 gD. 1000 g

The uncertainty in position and velocity of the particle are `0.1 nm` and `5.27 xx 10^-27 ms^-1` respectively. Then the mass of the particle is : `(h = 6.625 xx 10^-34 J s)`.A. 200 gB. 300 gC. 100 gD. 1000 g

The uncertainty in position and velocity of the particle are `0.2mm` and `10.54xx10^(-27)ms^(-1)` respectively then the mass of the particle is `: ( h=6.625xx10^(-34)Js)`A. `48.86g`B. `30.86g`C. `24.86gm`D. `100g`

If wavelength is equal to the distance travelled by the electron in one second thenA. `lambda = h//p`B. `lambda = h//m`C. `lambda = sqrt(h//p)`D. `lambda = sqrt(h//m)`

If wavelength is equal to the distance travelled by the electron in one second, thenA. `lambda=(h)/(p)`B. `lambda=(h)/(m)`C. `lambda=sqrt((h)/(p))`D. `lambda=sqrt((h)/(m))`

If wavelength is equal to the distance travelled by the electron in one second , then :A. `lambda = (h)/(p)`B. `lambda =(h)/(m)`C. `lambda = sqrt((h)/(p))`D. `lambda = sqrt((h)/(m)`

The mass number of three isotopes of an element are 10,12,14 units. Their percentage aboundance is 80,15 and 5 units respectively. What is the atomic weight of the element?

The value of the spin only magnetic moment of a particular ion is 2.83 Bohr magneton. The ion isA. `Fe^(2+)`B. `Ni^(2+)`C. `Mn^(2+)`D. `Co^(3+)`

Which of the following ion is not isoelectronic with `O^(2-)` ?A. `N^(3-)`B. `F^-`C. `TI^(+)`D. `Na^(+)`

Calculate the minimum uncertainty in velocity of a particle of mass `1.1 xx 10^-27 kg` if uncertainty in its position is `3 xx 10^-10 cm`.A. `1.5 xx 10^-4 m`B. `2.5 xx 10^-4 m`C. `3.5 xx 10^-4 m`D. `4.5 xx 10^-4 m`

If wavelength is equal to the distance travelled by the electron in one second, thenA. `lamda = (h)/(p)`B. `pi = (h)/(m)`C. `lamda = sqrt((h)/(p))`D. `lamda = sqrt((h)/(m))`

The relative atomic mass of an element A is 16.2 . There are two isotopes `""_(8)^(16)A` and `""_(8)^(18)A` of the element. Calculate the percentage of these two isotopes present in the element .

A naturally occuring sample of lithium contains 7.42% of `""^(6)Li` and 92.58% `""^(7)Li`. The relative atomic mass of `""^(6)Li` is 6.015 and that of `""^(7)Li` is 7.016. Calculate the atomic mass of a naturally occuring sample of lithium.

The hydride ions `(H^-)` are isoelectronic withA. `L i`B. `He^+`C. `He`D. `Be`

The hydride ion is isoelectronic with Electromagnetic RadiationA. `H^(+)`B. `He^(+)`C. HeD. Be

Which combinations of quantum number `n,l,m,s` for the electron in an atom does not provide a permission solution of the wave equation ?A. `3,2,-2,1//2`B. `3,3,1,-1//2`C. `3,2,1,1//2`D. `3,1,1,-1//2`

The ratio of the atomic numbers of two elements A and B is `2:3` A is an intery gas the first 3 orbits completely filled. Identify A and B and write their electronic configurations.

The hydride ions `(H^-)` are isoelectronic withA. LiB. `He^+`C. HeD. Be