(i) Calculate the number of electrons which will together weigh one gram.
(ii) Calculate the mass and charge of one mole of electrons.
(i) Mass of an electron = 9.1 x 10-28 g
Or
9.1 x 10-28 g contains = 1 electron
Therefore 1g contains = 1/9.1 x 10-28 *1 = 1.098 x 1027 electrons
(ii) We know, one mole of electron = 6.022 x 1023 electron
Mass of one electron = 9.1 × 10–28 g
Or
mass of 6.022 x 1023 electron = 9.1 x 10-28 x 6.022 x 1023 = 5.48 x 10-4 g
Charge on one electron = 1.6 × 10–19 coulomb
Charge on one mole of electron = (1.6 × 10–19 C x 6.022 × 1023)
= 9.63 × 104 C
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 wavelength of an electron moving with a velocity of 2.05 × 107 ms–1.
Using s, p, d notations, describe the orbital with the following quantum numbers.
(a) n = 1, l = 0;
(b) n = 3; l =1
(c) n = 4; l = 2;
(d) n = 4; l =3.
Which of the following are isoelectronic species i.e., those having the same number of electrons?
Na+, K+, Mg2+, Ca2+, S2–, Ar
Calculate the wavelength, frequency and wave number of a light wave whose period is 2.0 × 10–10 s.
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(b) n = 3, l = 0
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(i) CH2=C=O,
(ii) CH3CH=CH2,
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(iv) CH2=CHCN,
(v) C6H6
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(a) NaH2PO4
(b) NaHSO4
(c) H4P2O7
(d) K2MnO4
(e) CaO2
(f) NaBH4
(g) H2S2O7
(h) KAl(SO4)2.12 H2O
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(i) used to determine heat changes
(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.
A liquid is in equilibrium with its vapour in a sealed container at a fixed temperature. The volume of the container is suddenly increased.
a) What is the initial effect of the change on vapour pressure?
b) How do rates of evaporation and condensation change initially?
c) What happens when equilibrium is restored finally and what will be the final vapour pressure?
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(i) Lawrence Berkeley Laboratory
(ii) Seaborg’s group?
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2BrCl (g) ↔ Br2 (g) + Cl2 (g) for which Kc= 32 at 500 K.
If initially pure BrCl is present at a concentration of 3.3 × 10–3 mol L–1, what is its molar concentration in the mixture at equilibrium?
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(a) Li (b) Na (c) K (d) Cs
Thanks...
Thanks for the solution
Mass of e is 9.1 x 10^31 kg
Mr/Mrs cha,it's not necessary to take the mass of electron in kg only. We know that the mass of electron is 9.1*10^-28g or 9.1*10^-31kg so the solved question is right
Super
Mass of electron should be in kg
Mass of a electron is wrong here.It should be 9.1x 10^-31
Thnks alot
ððð
But mass of electron is 9.1 Ã10(-34)