Test Preparation on IIT JEE Mains Mock Test-5

CHEMISTRY
A solid has face centered cubic unit cell. If the
radius of the anion is 241.5 pm, the radius of the
cation is

1195 pm
2195 pm
3190 pm
490 pm

In a face centered cubic arrangement each ion is surrounded by six oppositely charged ions, i.e., coordination number is six. Radius ratio for coordination number 6 is 0.414 – 0.732.
when = r+/r- = 0.414 ; r+/241.5=0.414
r+ =0.414 x 241.5 = 99.98 = 100 when r+/r-= 0.732 ;
r+ =0.732 x 241.5 = 176.77 Radius of cation should be between 100 – 176.7 pm

The rate constant of a chemical reaction at 280K
is 1.6 x 10-6 s-1. The activation energy of this
reaction is zero. The value of k for this reaction
at 300K is

11.6 x 10-4 s-1
21.6 x 10-5 s-1
31.6 x 10-6 s-1
4zero

logk2/k1 =Ea/2.303R [1/T1-1/T2], Since energy of activation is zero, rate constant should be the same.

CH4(g) + 4CuO(s) → CO2(g) + 4Cu(s) + 2H2O(l)
For the above reaction at 298 K, _H°f in kJ mol-1
for CH4(g), CuO(s), CO2(g) and H2O(l) are
respectively -74.9, -157.3, -393.5 and -285.9 is. The
standard enthalpy change in kJmol-1 would be

1-1670
2-261
3+1670
4+261

CH4(g) + 4CuO(s)  CO2(g) + 4Cu(s) + 2H2O(l)
- 74.9 -4 x 157.3 -393.5 -2 x 285.9 -74.9 – 629.2 = -704.1 -393.5 - 571.8 = 965.3 Enthalpy change of the reaction
= - 965.3–(-704.1) = -261.2

A system at equilibrium is described by the
equation
Heat + SO2Cl2 (g)⇌ SO2(g) + Cl2(g)
The addition of Cl2 in the reaction mixture

1increases the temperature
2decreases the temperature
3has not effect on temperature
4decreases the volume

The addition of chlorine to the reaction mixture shifts the equilibrium backwards, thereby releasing more heat.

A solution of naphthalene in benzene has a mole
fraction of naphthalene equal to 0.10. What is the
molality of the solution?

12.3 m
21.42 m
33.1 m
41.9 m

Mole fraction of naphthalene = 0.1 mole fraction of benzene = 0.9;
Amount of benzene = 0.9 x 78 = 70.2 Molality of the solution =0.1x 1000/70.2 = 1.42 m

Polarisability of halide ions increases in the order

1F-, Cl-, Br-, l-
2Cl-, l-, Br-, F
3l-, Br-, Cl-, F-
4l-, Cl-, Br-, F-

Polarizability of halide ions increases with the increase in size of the anion.

The coagulation of 10 ml of gold solution is just
prevented by an addition of 1 ml of 10% NaCl in
the presence of 0.025 g. of starch. The gold
number of starch is:

10.25
20.025
325
4250

The gold number of a protective colloid is its minimum amount in milligrams which is just sufficient to prevent the coagulation of 10 ml of a gold sol on the addition of 1 mL of 10% sodium chloride solution. Amount in milligrams of 0.025 g. of starch is 25, so gold number is 25.

The total energy of a Bohr‟s orbit is proportional
to (n = Principal quantum number)

1n2
21/n
3n
41/n2

The total energy of a Bohr‟s orbit is proportional to 1/n2 .

Consider the following equilibrium:
NH4HS(s)⇌ NH3(g) + H2S(g)
Choose the correct relation:

1Kp = Kc (RT)1
2Kp = Kc (RT)2
3Kp = Kc (RT)3
4Kp = Kc

Kp = Kc(RT)Δn Δn = 2 – 0 = 2, therefore, Kp = Kc(RT)2


Right Ans	Wrong Ans	Not Attempted

CHEMISTRYA solid has face centered cubic unit cell. If theradius of the anion is 241.5 pm, the radius of thecation is

The rate constant of a chemical reaction at 280Kis 1.6 x 10-6 s-1. The activation energy of thisreaction is zero. The value of k for this reactionat 300K is

CH4(g) + 4CuO(s) → CO2(g) + 4Cu(s) + 2H2O(l)For the above reaction at 298 K, _H°f in kJ mol-1for CH4(g), CuO(s), CO2(g) and H2O(l) arerespectively -74.9, -157.3, -393.5 and -285.9 is. Thestandard enthalpy change in kJmol-1 would be

A system at equilibrium is described by theequationHeat + SO2Cl2 (g)⇌ SO2(g) + Cl2(g)The addition of Cl2 in the reaction mixture

A solution of naphthalene in benzene has a molefraction of naphthalene equal to 0.10. What is themolality of the solution?

Polarisability of halide ions increases in the order

The coagulation of 10 ml of gold solution is justprevented by an addition of 1 ml of 10% NaCl inthe presence of 0.025 g. of starch. The goldnumber of starch is:

The total energy of a Bohr‟s orbit is proportionalto (n = Principal quantum number)

Consider the following equilibrium:NH4HS(s)⇌ NH3(g) + H2S(g)Choose the correct relation:

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