IIT JEE: Chemistry model papers solved!

With the IIT JEE coming up on April 14, rediff.com in collaboration with SmartLearn present video tutorials in Maths, Physics and Chemistry to help test-takers give it their best shot.

Kicking off the series, we present four videos on Chemistry from the IIT JEE Model Paper 3.

Question 41: One gram of commercial AgNO3 is dissolved in 50 mL of water. It is treated with 50 mL of a KI solution. The silver iodide thus precipitated is filtered off. Excess of KI in the filtrate is titrated with M/10 KIO3 solution in presence of 6 M HCl till all I-ions are converted into ICl. It requires 50 mL of M/10 KIO3 solution. Twenty milliliters of the same stock solution of KI requires 30 mL of M/10 KIO3 under similar conditions. Calculate the percentage of AgNO3 in the sample.

Options:

(a) 85 (b) 80 (c) 75 (d) 90

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Which of the following statement/s with regard to quantum number is/are correct:

(a) The azimuthal quantum number gives the contribution of energy due to angular momentum towards the total energy of the electron

(b) The azimuthal quantum number gives the relative of energies of subshells belonging to the same shell

(c) The orbital angular momentum is given by azimuthal quantum number which is equal to

(d) The orbital angular momentum depends on the value of 'n'

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Mixed matrix type question

Column I
(A) Orthosilicate
(B) Pyrosilicate
(C) Single chain silicate
(D) Ring silicate

Column II
p. Oxygen atoms shared < 2
q. Oxygen atoms shared > 2
r. Net charge = -2
s. Net charge = -6

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Comprehension type question

When anions and cation approach each other, the valence shell of anions are pulled towards a cation, is known as polarisation and ability of the cation to polarize the anion is called as polarising power of cation. Due to polarisation, sharing of electrons occurs between two ions to some extent and bond shows some covalent character. Fajan's suggested following factors on which polarisation depends.

(i) As the charge on cation or anion increases polarisation increases.

(ii) Size of cation decreases or size of anion increases, polarisation increases.

(iii) Cation with pseudo noble gas configuration shows highest polarisation power.

55.Which is most covalent in nature
(a) NaCl
(b) MgCl2
(c) AlCl3
(d) CaCl2

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