The energy of the electron in the second and the third Bohr's orbits of the hydrogen atom is -5.42 $$\times$$ 10-12 erg and -2.41 $$\times$$ 10-12 erg respectively. Calculate the wavelength (in Å) of the emitted radiation when the electron drops from the third to second orbit.
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(C)
6603 Å
2
If 0.50 mol of BaCl2 is mixed with 0.20 mol of Na3PO4, the maximum amount of Ba3(PO4)2 that can be formed is
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(D)
0.10
3
1 mole of N2H4 loses 10 moles of electrons to form a new compound Y. assuming that all nitrogen appears in the new compound , what is the oxidation state of nitrogen in Y ? (there is no change in the oxidation state of hydrogen)
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(C)
+3
4
A 1.00 gm sample of H2O2 solution containing X percent H2O2 by weight requires X ml of a KMnO4 solution for complete oxidation under acidic conditions. Calculate the normality of the KMnO4 solution.
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(C)
0.588 N
5
Balance the following Equations:
(i) Cu2O + H+ + $$NO_3^ - \to $$ Cu2+ + NO + H2O
(ii) K4[Fe(CN)6] + H2SO4 + H2O $$\to$$ K2SO4 + FeSO4 + (NH4)2SO4 + CO
Rutherford's experiment on scattering of $$\alpha-particles$$ showed for the first time that the atom has
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(C)
nucleus
7
The correct order of second ionisation potential of carbon, nitrogen, oxygen and fluorine is
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(C)
O > F > N > C
8
The angle between two convalent bonds is maximum in ________. (CH4, H2O, CO2)
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(C)
CO2
9
If a molecule MX3 has zero dipole moment, the sigma bonding orbitals used by M (atomic number < 21) are
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(C)
sp2 hybrid
10
Equal weights of methane and oxygen are mixed in an empty container at 25oC. The fraction of the total pressure exerted by oxygen is
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(A)
1/3
11
The temperature at which a real gas obeys the ideal gas aws over a wide range of pressure is
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(B)
Boyle temperature
12
The ratio of root mean square velocity to average velocity of a gas molecule at a particular temperature is
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(A)
1.086:1
13
A solution of sodium metal in liquid ammonia is strongly reducing due to the presence of
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(D)
solvated electrons
14
Give reasons of the following:
Sodium carbonate is made by Solvay process but the same process is not extended to the manufacture of potassium carbonate.
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(A)
Potassium bicarbonate is more soluble than sodium bicarbonate, making it difficult to precipitate.
15
The vapour pressure of pure benzene is 639.7 mm of mercury and the vapour of a solution of a solute in benzene at the same temperature is 631.9 mm of mercury. Calculate this molality of the solution.
