Recent questions tagged physical-chemistry

The pair having identical value of $\large\frac{e}{m}$:

asked Jan 9, 2014 by sreemathi.v

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Find the wave length of radiation required to excite the electron in ground level of $Li^{++}(z=3)$ to third energy level.Also find the ionization energy of $Li^{2+}$.(R=$1.097\times 10^7m^{-1})$

asked Jan 9, 2014 by sreemathi.v

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Calculate the wave length of light radiation that would be emitted,when an electron in the fourth Bohr's orbit of $He^+$ ion falls to the second Bohr's orbit.To what transition does this light radiation correspond in the H-atom?

asked Jan 9, 2014 by sreemathi.v

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A spectral line in the spectrum of $H$-atom has a wave number of $15222.22cm^{-1}$. What transition is responsible for this radiation? (Rydberg constant $R=1.096\times 10^5cm^{-1}$)

asked Jan 9, 2014 by sreemathi.v

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Estimate the wavelength of second line (also called as $\beta$-line) in Balmer series of hydrogen atom

asked Jan 9, 2014 by sreemathi.v

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A hydrogen atom in the ground state is hit by a particle exciting the electron to 4s orbital.The electron then drops to 2s orbital.What is the frequency of radiation emitted and absorbed in the process?

asked Jan 9, 2014 by sreemathi.v

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Determine the frequency of revolution of the electron in $2^{nd}$ Bohr's orbit in hydrogen atom

asked Jan 9, 2014 by sreemathi.v

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Calculate the velocity of electron ejected from platinum surface when radiation of 200nm fall on it. Work function of platinum is 5eV. $(1eV=1.6\times 10^{-19}J$)

asked Jan 9, 2014 by sreemathi.v

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A 100W power source emits green light at a wavelength $\lambda=5000\overset{\circ}{A}$. How many photons per minute are emitted by the source?

asked Jan 9, 2014 by sreemathi.v

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Given the $\lambda$ values for violet light ($\lambda=4.10\times 10^{-5}cm)$ and red light($\lambda=6.56\times 10^{-5}cm$), which of the following is true about the ratio of energies carried by them and their frequencies?

asked Jan 9, 2014 by sreemathi.v

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Two elements A (atomic weight = 75) and B (atomic weight = 16) combine to yield a compound. The % by weight of A in the compound was found to be 75.08 . The formula of the compound is :

asked Jan 9, 2014 by sreemathi.v

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A compound was found to contain 5.37% nitrogen.What is the minimum molecular weight of compound?

asked Jan 9, 2014 by sreemathi.v

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The haemoglobin from the red blood corpuscles of most mammals contains approximately 0.33% of iron by weight.The molecular weight of haemoglobin as 67,200.The numbers of iron atoms in each molecule of haemoglobin is (at wt of iron=56)

asked Jan 9, 2014 by sreemathi.v

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Insulin contains 3.4% sulphur.The minimum mol weight of insulin is :

asked Jan 9, 2014 by sreemathi.v

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An ore contains 2.0% by weight of the mineral argentive $(Ag_2S)$.How much of ore should be taken to produce 1.0g pure Ag?

asked Jan 9, 2014 by sreemathi.v

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How many of $KCl$ would have to be dissolved in 60g $H_2O$ to give 20% by weight of solution?

asked Jan 9, 2014 by sreemathi.v

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The mole fraction of NaCl in a solution containing 1 mole of NaCl in 1000g of water is

asked Jan 9, 2014 by sreemathi.v

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Number of $H^+$ ions in 100ml of 0.001M $H_2SO_4$ is

asked Jan 9, 2014 by sreemathi.v

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