Important Paper JEE Advances

Q1. A metal surface is illuminated by light of two different wavelengths 248 nm and 310 nm. The maximum speeds of the photoelectrons corresponding to these wavelengths are u 1 and u 2 respectively. If the ratio u 1 : u 2 = 2 : 1 and hc = 1240 eV nm, the work function of the metal is nearly

1. 3.7 eV
2. 3.2 eV
3. 2.8 eV
4. 2.5 eV

Answer: A

Q2. Consider the partition to be rigidly fixed so that it does not move. When equilibrium is achieved, the final temperature of the gasses will be

1. 550 K
2. 525 K
3. 513 K
4. 490 K

Answer: D

Q3. Now consider the partition to be free to move without friction so that the pressure of gasses in both compartments is same. Then total work done by the gasses till the time they achieve equilibrium will be

1. 250R
2. 200R
3. 100R
4. -100R

Answer: D

Q4. Assuming 2s-2p mixing is not operative, the paramagnetic species among the following is

1. Be 2
2. B 2
3. C 2
4. N 2

Answer: C

Q5. The product formed in the reaction of SOCl 2 with white phosphorus is

1. PCl 3
2. SO 2 Cl 2
3. SCl 2
4. POCl 3

Answer: A

Q6. Hydrogen peroxide in its reaction with KIO4 and NH2OH respectively, is acting as a

1. reducing agent, oxidizing agent
2. reducing agent, reducing agent
3. oxidizing agent, oxidizing agent
4. oxidizing agent, reducing agent

Answer: A

Q7. The value of d in cm (shown in the figure), as estimated from Graham’s law, is

1. 8
2. 12
3. 16
4. 20

Answer: C

Q8. The experimental value of d is found to be smaller than the estimate obtained using Graham’s law. This due to

1. larger mean free path for X as compared of that of Y
2. larger mean free path for Y as compared of that of Y
3. increased collision frequency of Y with the inert gas as compared to that of X with the inert gas
4. increased collision frequency of X with inert gas as compared to that of Y with the inertgas

Answer: D

Q9. The correct statement with respect to product Y is

1. It gives a positive Tollen’s test and is a functional isomer of X
2. It gives a positive Tollen’s test and is a geometrical isomer of X
3. It gives a positive iodoform test and is a functional isomer of X
4. It gives a positive iodoform test and is a geometrical isomer of X

Answer: C

Q10. Three boys and two girls stand in a queue. The probability that the number of boys ahead of every girl is atleast one more than the number of girls ahead of her, is

1. 1/2
2. 1/3
3. 2/3
4. 3/4

Answer: A