Electromagnetic radiation of wavelength 242 nm is just sufficient to ionise the sodium atom. Calculate the ionisation energy of sodium in kJ mol–1.
From E= hv or hc/ λ, we have λ = 242nm or 242 x 10-9m
C = 3 x 108 m/s
h = 6.62 x 10-34 Js
Now putting these values in the equation we get
E= (6.62 x 10-34 Js x 3 x 108 m/s) / (242 x 10-9m)
= 0.0821 x 10-17 J/atom
Or
E = (0.0821 x 10-17 ) / (1000 x 6.02 x 1023)
= 494 KJ/mol
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Calculate the wavelength of an electron moving with a velocity of 2.05 × 107 ms–1.
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(a) n = 1, l = 0;
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(d) n = 4; l =3.
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(b) NaHSO4
(c) H4P2O7
(d) K2MnO4
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(g) H2S2O7
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(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.
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a) What is the initial effect of the change on vapour pressure?
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c) What happens when equilibrium is restored finally and what will be the final vapour pressure?
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(a) Li (b) Na (c) K (d) Cs
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(a) sp – sp2
(b) sp – sp3
(c) sp2 – sp3
(d) sp3 – sp3
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Nitric oxide reacts with Br2 and gives nitrosyl bromide as per reaction given below:
2NO (g) + Br2 (g) ↔ 2NOBr (g)
When 0.087 mol of NO and 0.0437 mol of Br2 are mixed in a closed container at constant temperature, 0.0518 mol of NOBr is obtained at equilibrium. Calculate equilibrium amount of NO and Br2 .
Thq a lot to give this answers
I have problem in dealing with numerical
Thank
Y
What about if use hydrogen instead of sodium
Tq saralstudy
Why cant we use -13.6Z^2
Why cant we use -13.6Z^2
How it's come?
Right solution