Indian Institute of Information Technology 2008 Entrance Exams IIT Entrance Exams IIT Study circle chemistry - Question Paper
IIT Study circle chemistry 2008
CHEMISTRY
Instructions: (1) Answer must be written either in
English or the medium of instruction of the candidate in high school.
1. The value of K (equilibrium constant,
rate constant, solubility constant) changes with temperature. But radioactive
decay constant is independent of temperature.
1. An equivalent in acid-base reaction and
an equivalent in oxidationreduction reaction
1. A fuel gas contains carbon and hydrogen only. Burning a small sample of it in oxygen gives 3.38 gm carbon dioxide, 0.69 gm of water and no other products. A volume of 10 lit (measured at STP) of this gas is found to weigh 11.6 gm. (a) Calculate 2. At a given temperature, the degree of ionization (fraction dissociated) of water is found to be 1.8x10-9. Calculate the ionization constant and the ionic product of water at this temperature. 3. Suppose the gas-phase isomerisation reactions
reach equilibrium at a fixed temperature. Express the equilibrium mole fractions of A,B and C in terms of equilibrium constants, K1, K2 and K3. 4. A sample of P2O5 contains some impurity. 0.405 gm sample is reacted with water and the resulting solution requires 42.5 ml of 0.25 M NaOH solution. The salt resulted is monobasic acid salt. Calculate the percent impurity. 5. What will be the resultant pH when 200 ml of an aqueous solution of HCl (pH=2) is mixed with 300 ml of an aqueous solution of NaOH (pH=12).
K=2 for the reaction at 10000C. If a 5L mixture contains 0.105 mole COF2, 0.22 mol CO2 and 0.055 mol CF4 at 10000C. (a) Will the mixture be at equilibrium? 7. For the reaction (i) A B ; Kc = 2 For the reaction A D what is the Kc? 8. Four elements coded A,B,C and D form a series of substances e.g. AB, B2, CB3, DB2 and DB3. If the atomic number of these elements are not necessarily in the order are 13, 19, 26 and 35. Write down extra nuclear electronic structures of these elements. From this information and the formula of the compounds, allocate A,B,C and D with appropriate atomic numbers. Mention the nature of bonding in each of them. 9. Calculate the molecular weight of hydrogen fluoride if density of this gas is 3.17 g/L at 300K and 1.0 atm pressure. What information can you deduce from the result? 10. Anhydrous copper sulphate turns to blue
from colourless on expose to atomosphere and again make it colourless by some
substance (X). When copper sulphate is added to water a blue colour solution
is resulted with some turbidity. The turbidity disappears by the addition of
a drop of HCl solution. On placing Iron rod in it, a greenish solution is
resulted. A chocolate like precipitate is resulted when a drop of potassium
ferrocyanide solution is added to the blue colour solution of copper
sulphate. Black precipitate is resulted by passing H2S gas through
copper sulphate solution but the precipitate is soluble in conc.HNO3. |
Earning: Approval pending. |