The Lucas test was carried out on three different compounds: A, B, and C. Compounds A and B were turbid at ambient temperature, while compound C did not become turbid until it was heated. Which one of the compounds is tertiary in structure?

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#Question id: 20133

#XL - P Chemistry

For the combustion of 1 mole of liquid benzene at 25ºC, the heat of reaction at constant pressure is given by, C6H6(l) + 7 O2 (g) → 6CO2 (g) + 3H2O (l); DH = –780980 cal.

What would be the heat of reaction at constant volume?

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#Question id: 20134

#XL - P Chemistry

Calculate the heat of formation of benzene from the following data, assuming no resonance. Bond energies :

C – C = 83 kcal = 140 kcal C – H = 99 kcal

Heat of atomisation of C = 170 .9 kcal

Heat of atomisation of H = 52.1 kcal

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#Question id: 20135

#XL - P Chemistry

Calculate ΔH at 358 K for the reaction

Fe2O3(s) + 3H2(g) → 2Fe (s) + 3H2O(l)

Given that, DH298= – 33.29 kJ mole^–1 and Cp for Fe₂O₃ (s), Fe (s), H₂O (l) and H₂ (g) are

103.8, 25.1, 75.3 and 28.8 J/K mole.

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#Question id: 20136

#XL - P Chemistry

Ka for CH3COOH at 25ºC is 1.754 × 10^–5 . At 50ºC, Ka is 1.633 × 10^–5 What will be value of Δ Sº for the ionisation of CH3COOH?

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#Question id: 20137

#XL - P Chemistry

If uncertainty in position and velocity are equal then uncertainty in momentum will be

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#Question id: 20138

#XL - P Chemistry

Number of waves made by a Bohr electron in one complete revolution in its fourth orbit is