Physical Chemistry MCQ with Answers

Physical Chemistry MCQ with Answers

211) The equilibrium constant for mutarotation of α−D glucose to β−D glucose is 1.8. What percent of the α−form remains under equilibrium?

Answer is:

35.7

212) When sulphur is in the form of S₈ is heated at 900 K, the initial pressure of 1 atm falls by 29% at equilibrium. This is because of conversion of some S₈ to S₂. Find the value of equilibrium constant for this reaction:

Answer is:

2.55 atm₃

213) What is the approximate OH⁻ ion concentration of a 0.15M NH₃ solution? (K_a = 1.75 x 10⁻⁵)

Answer is:

1.62 x 10⁻³

214) The vapour density of PCl₅ is 104.25 but when heated to 230^oC, its vapour density at this temperature will be:

Answer is:

0.68

Explanation:

α = (D − d)⁄d(y − 1)

215) When ammonia is added to pure water, the concentration of which of the following species already present, will decrease?

Answer is:

H₃⁺

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