For the reaction
2 A(g) + B(g) → 2D(g)
ΔU0 = –10.5 kJ and ΔS0 = –44.1 JK–1.
Calculate ΔG0 for the reaction, and predict whether the reaction may occur spontaneously.
For the given reaction,
2 A(g) + B(g) → 2D(g)
Δng = 2 - (3) = -1 mole
Substituting the value of ΔU0¸ in the expression of ΔH:
ΔHº = ΔUº + ΔngRT
= (-10.5 kJ) - (-1) (8.314 x 10-3 kJ K-1 mol-1) (298 K)
= -10.5 kJ - 2.48 kJ
ΔHº = -8.02 kJ
Substituting the values of ΔHº and ΔSº¸ in the expression of ΔH:
ΔGº = ΔHº - TΔSº
= -8.-02 kJ - (298 K) (-44.1 J K-1)
= -8.02 kJ + 13.14 kJ
ΔGº = + 5.12 kJ
Since ΔGº for the reaction is positive, the reaction will not occur spontaneously.
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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.
Calculate the wavelength of an electron moving with a velocity of 2.05 × 107 ms–1.
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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)
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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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(b) amber light from traffic signal
(c) radiation from FM radio
(d) cosmic rays from outer space and
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Write equations wherever necessary.
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Minus is kept two times in the 6th line its a mistake