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Tamanna Choudhury asked a question
Subject: Chemistry, asked on on 27/3/17
The Wave Number of the First Line Of Balmer Series Of Hydrogen Is 15200 Per Cm. The Wave Number Of The First Balmer Line Of Li(+2) Is i) 15200 Per Cm ii) 60800 Per Cm iii) 76000 Per Cm iv) 136800 Per Cm
Ragi Bhatt asked a question
Subject: Chemistry, asked on on 12/11/16
Be+3 and a proton are accelerated by the same potential their de Broglie wavelengths are in ratio of??
Tamanna Choudhury asked a question
Subject: Chemistry, asked on on 27/3/17
The Frequency Of One Of The Lines In Paschen Series Of A Hydrogen Atom Is 2.34 * 10(14) Hz. The Quantum Number, no Which Produces This Transition Is i) 3 ii) 4 iii) 6 iv) 5
Kartik Shinde asked a question
Subject: Chemistry, asked on on 5/7/17
When photons of energy 4.25 ev strike the surface of a metal A. The ejected photoelectrons have maximum kinetic energy (T(A) (expressed in ev) and de-Broglie wavelength (NA). The max kinetic energy of photoelectrons liberated from another Metal B by photons of enegy 4.2 eV is TB.Where TB (TA-1.5). If De-Broglie wave length of these photoelectrons AB (nB A), then which of the following is not correct (A) The work function of A is 2.25 eV. (B) The work function of B is 3.7 eV (C) TA=2.0 eV (D) TB=0.75 eV
Tamanna Choudhury asked a question
Subject: Chemistry, asked on on 28/3/17
The Ratio Of Radii Of 2nd, 4th And 6th Orbit Of Hydrogen Atom Is i) 2 : 4 : 6 ii) 1 : 4 : 9 iii) 1 : 4 : 6 iv) 1 : 3 : 2
Ragi Bhatt asked a question
Subject: Chemistry, asked on on 12/11/16
energy required to ionise 2 moles of gaseous He+ ion present in its ground state is??
Maitri C Trivedi asked a question
Subject: Chemistry, asked on on 19/6/17
THE ENERGY OF A PHOTON IS given as delta E / atom 3.03*10-19 J per atom . then the wavelength of the photon is ?
Sakshi asked a question
Subject: Chemistry, asked on on 3/10/16
a stream of electrons from heated filament was passed between two charged plates kept at potential difference V esu.If e and m are the charge and mass of an electron then find the value of h+lambda is given by​
Madhura Mandal asked a question
Subject: Chemistry, asked on on 4/7/17
The uncertainty in momentum of an electron is 1*10-5 kg m2/s. What will be the uncertainty in its position?
Ragi Bhatt asked a question
Subject: Chemistry, asked on on 12/11/16
the kinetic energy of an e- in H like atom is 6.04eV. the area of the 3rd Bohr orbit to which this e- belong is??
Kartik Shinde asked a question
Subject: Chemistry, asked on on 6/7/17
Work function WA for a photoelectric material A is 2 eV & WB for another photoelectric material B is 4 eV. If the photons of energy EA strike with surface of A the ejected photoelectrons have minimum de-Broglie length Lambda-A and photons of energy EB strike the surface of B, the ejected photoelectrons have minimum de-Broglie wavelength Lambda-B. Where EB=(EA+0.5) eV and Lambda-B=2(Lambda-A), VA and VB are respective stopping potentials then which of the following is not correct (A) EA=4 ev (B) EA=4.5 eV (C) VA=2 Volts (D) VB=0.5 Volts
Gurnoor Bedi asked a question
Subject: Chemistry, asked on on 18/10/16
if we plot a graph of frequency of radiation against the stopping potential of photoelectron, its slope would be
  1. 6.625 * 10^-34
  2. 3.656 * 10^12
  3. 2.414 * 10^14
  4. 6.529 * 10^18
Madhura Mandal asked a question
Subject: Chemistry, asked on on 14/7/17
in chromium atom, in ground state , find the number of occupied orbitals.
Chirag Agrawal & 1 other asked a question
Subject: Chemistry, asked on on 6/8/17
the wavelength of de Broglie of electron revolving in 5th orbit of hydrogen atom is r0 in Bohr orbit.{radius=0.529A}
Sadiya Khan asked a question
Subject: Chemistry, asked on on 25/4/17
Ans question no 16
Akash Deep asked a question
Subject: Chemistry, asked on on 31/5/17
electron present in single electron specie jumps from level 3 to 1.emitted photons when passed through a sample containing excited He+ion causes further excitation to some higher energy level.Determine atomic number of single electron specie.
Madhura Mandal asked a question
Subject: Chemistry, asked on on 14/7/17
In magnesium atom, in ground state, what is the number of electrons with m=0?
Kartik Shinde asked a question
Subject: Chemistry, asked on on 6/7/17
Light of the prominent mercury line 2357A ejects electrons from a metal surface, that have stopping potential of 2.6 volts. The stopping potential of electrons ejected from the same metal by the other prominent mercury line 1849A is 4.04 volts. a) Calculate the value of Planck s constant b) Calculate the value of threshold frequency using these data
Akash Deep asked a question
Subject: Chemistry, asked on on 31/5/17
the correct order of wavelength of hydrogen, deuterium, tritium moving with same kinetic energy is?
Haseena Vannanchalil asked a question
Subject: Chemistry, asked on on 15/3/17
s-orbital is spherically symmetricla hence
  • a it is directional independent
  • b angular independent
  • c both (a) and (b)
  • d None of the above


 
Saraswati Palnitkar asked a question
Subject: Chemistry, asked on on 16/10/16
Atomic no. of calcium is 20. so its electronic configuration should be 2,8,10 as the M shell can accomodate 18 electrons.
Then why is it 2,8,8,2??
Calcium is just an example. I cant understand how Bohr's second rule can conflict with his 1st?
Bipasha Ghosh asked a question
Subject: Chemistry, asked on on 23/3/17
Why an orbital can not hold more than 2 electrons?
Ragi Bhatt asked a question
Subject: Chemistry, asked on on 15/11/16
if radius of 3rd orbit of Li+2 ion is x then de-Broglie wavelength of electron in 2nd orbit of He+ is?? fasssttttt
Sadiya Khan asked a question
Subject: Chemistry, asked on on 25/4/17
Ans question no2
Sakshi asked a question
Subject: Chemistry, asked on on 3/10/16
how many maximum spectral lines can be expected in visible electronic transition from fifth shell to first shell of H2 atom of 2 atom
Arundhati Santosh asked a question
Subject: Chemistry, asked on on 28/8/17
A table tennis ball has a mass 10 g and a speed of 90 m\s. if speed can be measured within an accuracy of 4% what will be the uncertainty in speed and position?
Sadiya Khan asked a question
Subject: Chemistry, asked on on 1/5/17
Ans question no 5 and 6
Akash Deep asked a question
Subject: Chemistry, asked on on 31/5/17
the de broglie wavelength of the electron ejected out when the radiation of energy 'E' strikes on the metal surface having threshold frequency equal to half of incident frequency is?
Ragi Bhatt asked a question
Subject: Chemistry, asked on on 12/11/16
which one of the following is nearest to the nucleus??
1) 6s
2) 7p
3) 4f
4) 5d
Madhura Mandal asked a question
Subject: Chemistry, asked on on 11/7/17
A n isotope of atomic mass 25 has 13 neutrons in the nucleus. What is its atomic number, and what are the name and chemical symbol of the element?
Sakshi Satpute asked a question
Subject: Chemistry, asked on on 20/1/17
Ionization energy of He+ is 19.6 x 10-18 J atom-1 . The energy of the first stationary state ( n=1 ) of Li2+ is....?
Abhishek Paul asked a question
Subject: Chemistry, asked on on 17/5/17
Please explain how to differentiate between the cause of torsional strain & vanderwaal strain.
Sadiya Khan asked a question
Subject: Chemistry, asked on on 25/4/17
Ans question no 44
Sadiya Khan asked a question
Subject: Chemistry, asked on on 25/4/17
Ans question no 14
Akash Deep asked a question
Subject: Chemistry, asked on on 31/5/17
1.6g sample of He+ ​ions are excited to emit radiations . Spectral study of sample indicates that highest excited state is 2nd and that total no of ions in 1st and 2nd​ excited state is one third of ions in ground state.Total energy evolved on de-excitation of sample is 429.5kJ.Let X be the percentage of He + ions in second excited stage in original sample .Find the value of [X/6.25]
Sakshi Satpute asked a question
Subject: Chemistry, asked on on 20/1/17
Uncertainity in the position of an electron ( mass =91 x 10-31kg ) moving with a velocity 300 ms-1 accurate upto 0.001% wil be.....?
Abhishek Paul asked a question
Subject: Chemistry, asked on on 17/5/17
Please explain the basic strength order of the 2nd question-
Arundhati Santosh asked a question
Subject: Chemistry, asked on on 28/8/17
which has a higher energy - a photon of red light with wavelength 7600 A or a photon of green light with wavelength 5250 A?
Madhura Mandal asked a question
Subject: Chemistry, asked on on 14/7/17
what is the maximum number of electrons in K atom with quantum number (n=3, m=+1 amd s=+1/2)?
Abhishek Paul asked a question
Subject: Chemistry, asked on on 17/5/17
Please explain.
Saipriya asked a question
Subject: Chemistry, asked on on 14/6/17
only few substances are found in free state in nature.explain
Abhishek Paul asked a question
Subject: Chemistry, asked on on 2/5/17
Please explain in detail-
Saipriya asked a question
Subject: Chemistry, asked on on 14/6/17
salt is a compound of sodium and chlorine explain that salt has different properties than it's constituent element 
Akshat Kant Thakur asked a question
Subject: Chemistry, asked on on 15/9/17
whe we have to write 0.057 *10^-3 in the form of 5.7 then wht is the power of 10 please explain how to do it and remembe it
Reminjavad asked a question
Subject: Chemistry, asked on on 20/2/17
​ .
Sakshi Satpute asked a question
Subject: Chemistry, asked on on 20/1/17
The measurement of the electron position is associated in momentum which is equal to 1 x 10-8 g cm-1 . The uncertainty in electron velocity is ....(mass of an electron is 9 x 10-28 g )
Akshat Kant Thakur asked a question
Subject: Chemistry, asked on on 15/9/17
how to shift the decimal point of  very big no. with powers of 10 in positive and negative in small no. like 5.65*10^84 lease explain briefly

 
Haseena Vannanchalil asked a question
Subject: Chemistry, asked on on 15/3/17
For an orbital with value l = 1,it will be symmetric about
  • ​a either x,y or z axis
  • b the x axis only
  • c the nucleus
  • d it is unsymmetric
Saipriya asked a question
Subject: Chemistry, asked on on 14/6/17
water is a compound but sugar or salt make a mixture when dissolved in water.explain
Abhishek Paul asked a question
Subject: Chemistry, asked on on 9/5/17
Please explain (5) in detail.(Assertion-Reason)
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