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
The mass of an electron is 9.1 × 10–31 kg. If its K.E. is 3.0 × 10–25 J, calculate its wavelength.
Calculate the amount of carbon dioxide that could be produced when
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(ii) 1 mole of carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
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(b) MnO4 – (aq) + SO2 (g) → Mn2+ (aq) + HSO4– (aq) (in acidic solution)
(c) H2O2 (aq) + Fe 2+ (aq) → Fe3+ (aq) + H2O (l) (in acidic solution)
(d) Cr2O7 2– + SO2(g) → Cr3+ (aq) + SO42– (aq) (in acidic solution)
In a process, 701 J of heat is absorbed by a system and 394 J ofwork is done by the system. What is the change in internal energy for the process?
What will be the minimum pressure required to compress 500 dm3 of air at 1 bar to 200 dm3 at 30°C?
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(i) 300 atoms of A + 200 molecules of B
(ii) 2 mol A + 3 mol B
(iii) 100 atoms of A + 100 molecules of B
(iv) 5 mol A + 2.5 mol B
(v) 2.5 mol A + 5 mol B
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(i) 1 g Au (s)
(ii) 1 g Na (s)
(iii) 1 g Li (s)
(iv) 1 g of Cl2(g)
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1Pa = 1N m–2
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(i) Lawrence Berkeley Laboratory
(ii) Seaborg’s group?
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Apart from tetrahedral geometry, another possible geometry for CH4 is square planar with the four H atoms at the corners of the square and the C atom at its centre. Explain why CH4 is not square planar?
What will be the mass of one 12C atom in g?
(i) Calculate the total number of electrons present in one mole of methane.
(ii) Find
(a) the total number and
(b) the total mass of neutrons in 7 mg of 14C. (Assume that mass of a neutron = 1.675 × 10–27 kg).
(iii) Find
(a) the total number and
(b) the total mass of protons in 34 mg of NH3 at STP.
Will the answer change if the temperature and pressure are chang
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H2O(s) + F2(g) → HF(g) + HOF(g)
Justify that this reaction is a redox reaction.
What is the difference between distillation, distillation under reduced pressure and steam distillation ?
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