Calculate the total pressure in a mixture of 8 g of dioxygen and 4 g of dihydrogen confined in a vessel of 1 dm3 at 27°C. R = 0.083 bar dm3 K–1 mol–1.
Given,
Mass of oxygen = 8 g, molar mass of oxygen = 32 g/mol
Mass of hydrogen = 4 g, molar mass of hydrogen = 2 g/mol
Therefore amount of oxygen = 8/ 32 = 0.25 mol
And amount of hydrogen = 4/2 = 2 mol
From the gas equation PV = n RT, we get,
P X 1 = (0.25 + 2) X 0.083 X 300 = 56.02 bar
Hence, the total pressure of the mixture is 56.02 bar.
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(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
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(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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(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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(ii) zero
(iii) < 0
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(iii) not possible at any temperature
(iv) possible at any temperature
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