CHEMISTRY
PAPER – 1
(Three Hours)
Question 1
(a) Fill in the blanks by choosing the appropriate word/words from those given in the brackets:
(hydrolysis, reduction, oxidation, vacant, osmotic, above, benzoic acid, phenol, aniline, below, can, decreases, increases, cannot, crystal, ionization, rate, rate constant.)
(i) A catalyst ______ start a reaction but it can increase the ______ of the reaction.
(ii) Electrons trapped in the ______ sites of the __________ lattice are called F-centres.
(iii) An aqueous solution of sugar boils ________ 100oC and freezes _______ 0oC.
(iv) Toluene on ________ with alkaline potassium permanganate gives________.
(v) The degree of _________ of ammonium hydroxide ________ on addition of ammonium chloride.
(b) Complete the following statements by selecting the correct alternative from the choices given:-
(i) For reaction 2N2O5 --> 2 NO2 + O2, the rate and rate constants are 1.02 ×10-4 mole litre-1 sec-1 and 3.4 ×10-5 sec-1 respectively. The concentration of N2O5 at that time will be:
(1) 1.732 mol litre-1
(2) 3 mol litre-1
(3) 1.02×10-4 mol litre-1
(4) 3.2×105 mol litre-1
(ii) Ethanoic acid dimerises in solution. Its molecular mass determined from its depression of freezing point of the solution will be:
(1) Same as the theoretical value
(2) Half its theoretical value
(3) Double its theoretical value
(4) One third of its theoretical value.
(iii) Magnesium displaces hydrogen from dilute acid solution because:
(1) The oxidation potential of magnesium is less than that of hydrogen.
(2) The reduction potential of magnesium is less than that of hydrogen.
(3) Both magnesium and hydrogen have same oxidation potential.
(4) Both magnesium and hydrogen have same reduction potential .
(iv) In the reaction PCl3(g) + Cl2(g) --> PCl5(g), the equilibrium will shift in the opposite direction, if:
(1) Chlorine is added.
(2) PCl3 is added
(3) Pressure is increased
(4) Pressure is reduced.
(c) Answer the following questions:
Please refer to attached file for ISC Question Papers 2013 Chemistry