Phenolphthalein is not suitable for the titration of :

• NaOH vs (COOH)₂

• KOH vs H₂SO₄

• K₂CO₃ vs HCl

• none of the above

12.

For a gaseous reaction,

C₂H₄ + H₂ $\rightleftharpoons$ C₂H₆ ; $∆$H = -32.7 Kcal.

The concentration of C₂H₄ can be decreased by :

• increasing pressure

• increasing amount of H₂

• decreasing temperature

• all of these

PCl₅ was heated in a 10 dm³ container at 250°C

PCl₅(g) $\rightleftharpoons$ PCl₃(g) + Cl₂ (g)

0.1 mol PCl₅ and 0.2 mol Cl₂ was found at equilibrium. The equilibrium constant for the reaction is :

• 0.025

• 0.04

• 0.02

• 0.05

In the reaction,

H₂SO₄ + H₂O $\rightleftharpoons$ H₃O⁺ + HSO₄^-,

the conjugate acid of water is :

• H₃O⁺

• H₂O

• HSO₄^-

• SO₄^2-

36 g water and 828 g ethyl alcohol form an ideal solution. The mole fraction of water in it, is :

• 1.0

• 0.7

• 0.4

• 0.1

Hydrogen in respect to chlorine, is :

• electropositive

• electronegative

• neutral

• none of the above

Which of the follownig elements, is most electronegative ?

• F

• O

• Ne

• Na

What is obtained , when propene is treated with N-bromo succinimide ?

• CH₃-CBr=CH₂

• BrCH₂-CH=CH₂

• BrCH₂-CH=CHBr

• BrCH₂-CHBr-CH₂Br

Poisonous gas 'Lewisite' is obtained by the reaction of :

• CH$\equiv$CH and AsCl₃

• CH₂=CH₂ and AsCl₃

• CH$\equiv$CH and S₂Cl₂

• CH₂=CH₂ and NOCl

What will be the main product, when benzene vapours are passed over V₂O₅ at 450°C ?