MEDIUM
JEE Main/Advance
IMPORTANT
Earn 100

Suppose 10-17 J of light energy is needed by the interior of the human eye to see an object. How many photons of green light λ=550 nm are needed to generate this minimum amount of energy?

Given :hcλ=1240λ in nm

Important Questions on Structure of Atom

EASY
JEE Main/Advance
IMPORTANT

10x number of photons of radiation of frequency 5×1013 s-1 that must be absorbed in order to melt one g ice when the latent heat of fusion of ice is 330 J/g. Find value of x.

Use: Planck's constant =6.626×10-34Js

MEDIUM
JEE Main/Advance
IMPORTANT

If threshold frequency of metal is 4.5×10xsec-1 and binding energy is 180.69 kJ mol-1 of electron. Then find value of x.

Use: Planck's constant =6.626×10-34Js

EASY
JEE Main/Advance
IMPORTANT

Calculate the binding energy per mole when threshold wavelength of photon is 240 nm.

Use: Planck's constant =6.626×10-34Js

Round off your answer to the nearest integer.

MEDIUM
JEE Main/Advance
IMPORTANT

The reaction between H2 and Br2 to form HBr in presence of light is initiated by the photo decomposition of Br2 into free Br atoms (free radicals) by absorption of light. The bond dissociation energy of Br2 is 192 kJ/mole. If the longest wavelength of the photon that would initiate the reaction is yA. Then find value of y.

Use: Planck's constant=6.62×10-34Js and Avogadro's number =6.02×1023

MEDIUM
JEE Main/Advance
IMPORTANT

The quantum yield for decomposition of HI is 0.2. In an experiment 0.01 moles of HI are decomposed. If the number of photons absorbed is 3×10x. Then find value of x.

Use : Avogadro's number 6.02×1023

MEDIUM
JEE Main/Advance
IMPORTANT
To what series does the spectral lines of atomic hydrogen belong if its wave number is equal 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 this line?
EASY
JEE Main/Advance
IMPORTANT
Find the quantum number n corresponding to the excited state of He+ ion, if on transition to the ground state that ion emits two photons in succession with wave lengths 108.5 and 30.4 nm.
EASY
JEE Main/Advance
IMPORTANT
A hydrogen like atom (atomic number Z) is in a higher excited state of quantum number n. This excited atom can make a transition to the first excited state by successively emitting two photons of energies 10.20 eV and 17.00 eV, respectively. Alternatively, the atom from the same excited state can make a transition to the second excited state by successively emitting two photons of energies 4.25 eV and 5.95 eV, respectively. Determine the values of n and Z. (Ionization energy of hydrogen atom=13.6 eV)