(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.
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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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(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?
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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% Natural Abundance | Molar Mass | |
35Cl | 75.77 | 34.9689 |
37Cl | 24.23 | 36.9659 |
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(iii) molecular formula.
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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
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But mass of electron is 9.1 Ã10(-34)