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Siddharth Rathore asked a question
Subject: Chemistry, asked on on 29/5/16
The angular momentum of an electron in a given orbit is J, Its Kinetic Energy will be?
Abhidha Anil asked a question
Subject: Chemistry, asked on on 28/5/17
What is the relation between angstrom and eV
Siddharth Rathore asked a question
Subject: Chemistry, asked on on 29/5/16

A single electron ion has charge+Ze where Z is atomic number and e is electronic charge. it requires 16.52eV to excite the electron from the second Bohr orbit to third Bohr orbit. find

 

- Atomic number of element

 

- The energy required for transition of electron from first to third orbit

 

- Wavelength of photon required to remove electron from first Bohr orbit to infinity

 

- The Kinetic Energy of electron in first Bohr orbit
Samiksha Jain asked a question
Subject: Chemistry, asked on on 5/6/16
the orbital angular momentum quantum number of the state S2 is
a.0
b.1
c.2
d.3
Arun Sharma asked a question
Subject: Chemistry, asked on on 11/8/17
Angular momentum for P-shell electron is:- 1) 3h/pi 2) Zero 3) (root2)h/2pi 4) None (Answer is given as 1 but how? Please help.)
Neelabh asked a question
Subject: Chemistry, asked on on 12/6/16
I have the question: The speed of a certain proton is 0.45 Mm/s. If the uncertainty in its momentum is to be reduced to 0.0100 percent, what uncertainty in its location must be tolerated?The ans is 0.70 nm . Pls explain the solution
Bikeracer asked a question
Subject: Chemistry, asked on on 4/7/17
calculate the  energy in calorie required to produce, from neutral He atoms, 1 mole of 
a)He= ions 
b) He++ ions                          Using Bohr's equations.
Pankaj Mandrawal asked a question
Subject: Chemistry, asked on on 23/6/16
​Threshold frequency of potassium is 3*10^14 Hz. Find  the work function(in joules).​
Arun Sharma asked a question
Subject: Chemistry, asked on on 3/8/17
Which of the following elements has maximum density of nucleus:
a) Si ( A = 30, Z = 14)
b) P ( A = 31, Z = 15)
c) O ( A = 16, Z = 8)
d) All have same density.
Akanksha Chauhan asked a question
Subject: Chemistry, asked on on 11/4/17
(n+1) is the principal quantum number of the energy state for an atom. what are the number of elliptical orbits associated with it:
1. (n-1)
2. (n+1)
3. (n-2)
4. n
Samiksha Jain asked a question
Subject: Chemistry, asked on on 31/5/16
Light from a discharge tube containing hydrogen atoms falls on the surface of a piece of sodium. The kinetic energy of the fastest photoelectrons emitted from sodium is 0.73 eV. The work function for sodium is 1.82 eV. Find (a) the energy of the photons causing the photoelectric emission,
(b) the quantum numbers of the two levels involved in the emission of these photons,
Upanshu Srivastava asked a question
Subject: Chemistry, asked on on 26/6/16
THE BRIGHTNESS OR INTENSITY OF SPECTRAL LINES DEPENDS UPON THE NUMBER OF PHOTONS OF SAME WAVELENTH OR FREQUENCY ABSORBED OR EMITTED
EXPLAIN THIS LINE
Dhruvin Pandya asked a question
Subject: Chemistry, asked on on 8/10/18

Total number of lines emitted in infrared region when electron is de-excited from 5thexcited state to ground state in hydrogen atom
Shivanshu Kant asked a question
Subject: Chemistry, asked on on 14/5/16
How do they came to know that whether the alpha particles are positively charged
Samiksha Jain asked a question
Subject: Chemistry, asked on on 2/6/16
an excited hydrogen like species when bombarded by photons of wavelength 54 nmgets excited to another excited state. in returning back to ground state a total of six different type of photons were emitted.out of 6 photons three have wavelength less than 54 nm. determine
a.initial and final excited state
b.ionization energy
c.atomic number
Harsh Sharma asked a question
Subject: Chemistry, asked on on 28/10/16
To what series does the spectral lines of atomic hydrogen belong if its wave number is equal to the difference between the wave numbers of the following two lines of the Balmer series. 486.1 and 410.2 nm? What is the wavelength of that line? 
Samiksha Jain asked a question
Subject: Chemistry, asked on on 31/5/16
an excited hydrogen like species when bombarded by photons of wavelength 54nm,gets excited to another excited state. in returning back to ground state , a total of six different types of photons were emitted. out of 6 photons three have wavelength less than 54 nm. determine
a. initial and final excited state
b.ionization energy
c. atomic number
Greeshma V S asked a question
Subject: Chemistry, asked on on 25/5/16
what is isodiasphere? and explain with more example ? and also tell that for which element isodiaspherewill exist
Awantika Srivastava asked a question
Subject: Chemistry, asked on on 16/11/16
5ml of a gaseouss hydrocarbon was exposed to 30 ml of o2 the resultant gas on cooling was found to measure 25 ml of which10ml are absorbed by NaOH and the remainder by pyrogallal. determine molecular formula of hydrocarbon. all measurement are taken at constant temp. and pressure
Samiksha Jain asked a question
Subject: Chemistry, asked on on 31/5/16
find the circumference of the fifth bohr orbit of an electron whose de-brogile wavelength corresponds to translation kinetic energy of h at 27 degree celsius
Almas asked a question
Subject: Chemistry, asked on on 29/11/16
xCr2O72- + ySO2 -----> Cr3+ + SO42-
the x and y in the reaction are ?
Prasad Kumkar asked a question
Subject: Chemistry, asked on on 6/6/16
can't we add o2 directly instead of adding h2o?? ..in dat balancing eqn
Sushobhit asked a question
Subject: Chemistry, asked on on 10/7/17
If dz2 orbital can exist then why not dy2 or dx2 although there r only 5 maximum possible l values
Saatwik Sharma asked a question
Subject: Chemistry, asked on on 5/2/17
  1. Calculate the molar mass of C2O5OH  
Sakshi Srivastava asked a question
Subject: Chemistry, asked on on 25/5/17
1/4pi*​epsilon naught+(ze)(e-)/r2=me ve2/r. in this equation what does (ze) stand for?
Sanju Suresh asked a question
Subject: Chemistry, asked on on 21/5/16
In rutherfords model, one of the drawbacks of it was put forward by maxwell i.e."any charged particle loses energy due to acceleration(when the electron is revolving around the nucleus, it is constantly changing direction, thus undergoing acceleration". so if the electrons lose energy, it will spiral into the nucleus and the atom will be unstable(which does not happen). Is this right? because in the live class, Sir gave another explanation...
Vaishnavi asked a question
Subject: Chemistry, asked on on 2/7/17
where do we use the formula E=nhv(nu) hc(nu-bar)
Dania Eapen asked a question
Subject: Chemistry, asked on on 19/5/16
What is the difference between fluorescence and phosphoresence ?
Samiksha Jain asked a question
Subject: Chemistry, asked on on 31/5/16
photochemical dissociation produces a normal oxygen atom and an oxygen atom 2.5ev more energetic than normal one. also the average bond energy of oygen itno noraml oxygen is 498kj/mol. determine the longest wavelength required for photochemical dissociation of oxygen.
Prithesh Dwivedi asked a question
Subject: Chemistry, asked on on 10/6/16
The ionization potential for the electron in the ground state of the hydrogen atom is 13.6 eV/atom. What would be the ionization potential for the electron in the first excited stste of Li2+.
(a) 3.4 eV
(b) 10.2 eV
(C) 30.6 eV
(D) 6.8 eV
Medha asked a question
Subject: Chemistry, asked on on 25/5/16
sir this is the practice question of the lst cls tat i dnt got can u jst give a hint for the question-
''A GAS ABSORBS A PHOTON OF WAVELENGTH OF 350 nm AND THEN RE EMITS TWO PHOTONS. IF ONE RE-EMITTED PHOTON HAS A WAVELENGTH OF 650nm, THEN CALCULATE THE ENERGY OF OTHER RE-EMITTED PHOTON?????''
Akanksha Chauhan asked a question
Subject: Chemistry, asked on on 11/4/17
an electron is in one of 4d orbital .which of the following orbital quantum number value is not possible
1. n = 4
2. l = 1
3. m = 1
4. m = 2
Aditi Nandi asked a question
Subject: Chemistry, asked on on 22/5/16
in the formulae hnu=hnu0 + 1/2 mv^2 which is the ionization enthalpy?
Saloni Kenguva asked a question
Subject: Chemistry, asked on on 1/6/16
In photoelectriceffect if the the frequency of the light used is equal to the threshold frequency of the metal then what happens to the electron produced because if threshold frequency is equal to frequency of light then e-will have no KE so wont that mean that they wont be ejected
Greeshma V S asked a question
Subject: Chemistry, asked on on 3/6/16
in telvisionthe cathode rays are used instead of anoderays why ?
Sneha Elsa Thomas asked a question
Subject: Chemistry, asked on on 18/5/16
Why IS EM RADIATIONnot deflected???
Anusree Jk asked a question
Subject: Chemistry, asked on on 6/7/16
What is the difference between radial probability function and probability distribution function?
Almas asked a question
Subject: Chemistry, asked on on 15/3/17
Which transition in H atom will emit maximum frequency of photon ?
a) n=4 to n=1
b) n=2 to n=1
c) n=4 to n=2
d) n=1 to n=5
Vaishnavi asked a question
Subject: Chemistry, asked on on 2/7/17
where do we use the formula Eev/atom(which is =12400)...give me an example...
Guna Shekar asked a question
Subject: Chemistry, asked on on 3/10/17
In an atom total number of electrons having quantum numbers n=4, |ml|=1 , ms = -1/2 is?
Arun Sharma asked a question
Subject: Chemistry, asked on on 2/8/17
In C12 atom if mass of electron is doubled and mass of proton is halved, then calculate the percentage of change in the mass number of C12. (Ans is given as 25%)
Alok Singh asked a question
Subject: Chemistry, asked on on 1/6/17
THE ELECTRONIC CONFIGURATION OF SILICON IS GIVEN AS 1s​2 2s22p63s2 3p2 . IN THIS CONFIGURATION WHY DOES NOT ONE ELECTRON FROM THE 3s2ORBITAL GO TO 3p2 ORBITAL TO ATTAIN MAXIMUM STABILITY AS ELECTRONS IN A HALF FILLED ORBITAL ARE MORE STABLE?
Samiksha Jain asked a question
Subject: Chemistry, asked on on 31/5/16
a hydrogen atom with an electron in the first shell absorbs uv light of wavelength 1.03*10-3m. to what shell does the electron jump
Sangeeta Jha asked a question
Subject: Chemistry, asked on on 16/8/16
which one of the following will have higher ionisation enthalpy-
  1. argon and krypton
  2. carbon and nitrogen 
Aryan asked a question
Subject: Chemistry, asked on on 16/7/17
What is 'colatitude' in chemistry?
Sangeeta Jha asked a question
Subject: Chemistry, asked on on 14/8/16
Plzz tell the ans of Q10..
Pianist asked a question
Subject: Chemistry, asked on on 25/7/17
If the potential energy of Electron in the first orbit of Bohr atomic model is considered to be 0, then find out the total energy.
Anuj asked a question
Subject: Chemistry, asked on on 8/1/17
acc to Maxwell's discovery of electromagnetic waves( charged particle when accl under mf or ef produces radiations)all particles or substances should radiate when under mf or ef as all have electrons as charged particle.So why don't they do so
Anuj asked a question
Subject: Chemistry, asked on on 23/5/17
If a ques is asked that find value of quantum numbers of electron in 2s orbital so for the electrons in 2s orbitals will azimuthal quantum number be 1 or 0...because here n=2 
Pianist asked a question
Subject: Chemistry, asked on on 28/7/17

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