NEET-UG 2021 · Code M1

Dihedral angle of least stable conformer of ethane is :

1. A120°
2. B180°
3. C60°
4. D0°

Noble gases are named because of their inertness towards reactivity. Identify an incorrect statement about them.

1. ANoble gases are sparingly soluble in water.
2. BNoble gases have very high melting and boiling points.
3. CNoble gases have weak dispersion forces.
4. DNoble gases have large positive values of electron gain enthalpy.

A particular station of All India Radio, New Delhi, broadcasts on a frequency of 1,368 kHz (kilohertz). The wavelength of the electromagnetic radiation emitted by the transmitter is : [speed of light, c=3.0×10⁸ ms⁻¹]

1. A219.3 m
2. B219.2 m
3. C2192 m
4. D21.92 cm

The incorrect statement among the following is :

1. AActinoid contraction is greater for element to element than Lanthanoid contraction.
2. BMost of the trivalent Lanthanoid ions are colorless in the solid state.
3. CLanthanoids are good conductors of heat and electricity.
4. DActinoids are highly reactive metals, especially when finely divided.

Right option for the number of tetrahedral and octahedral voids in hexagonal primitive unit cell are :

1. A8, 4
2. B6, 12
3. C2, 1
4. D12, 6

Which of the following reactions is the metal displacement reaction ? Choose the right option.

1. A2KClO₃ → 2KCl+3O₂
2. BCr₂O₃+2Al → Al₂O₃+2Cr
3. CFe+2HCl → FeCl₂+H₂↑
4. D2Pb(NO₃)₂ → 2PbO+4NO₂+O₂↑

Given below are two statements : Statement I : Aspirin and Paracetamol belong to the class of narcotic analgesics. Statement II : Morphine and Heroin are non-narcotic analgesics. In the light of the above statements, choose the correct answer from the options given below.

1. ABoth Statement I and Statement II are true.
2. BBoth Statement I and Statement II are false.
3. CStatement I is correct but Statement II is false.
4. DStatement I is incorrect but Statement II is true.

Statement I : Acid strength increases in the order given as HF << HCl << HBr << HI. Statement II : As the size of the elements F, Cl, Br, I increases down the group, the bond strength of HF, HCl, HBr and HI decreases and so the acid strength increases. In the light of the above statements, choose the correct answer from the options given below.

1. ABoth Statement I and Statement II are true.
2. BBoth Statement I and Statement II are false.
3. CStatement I is correct but Statement II is false.
4. DStatement I is incorrect but Statement II is true.