- The maximum number of electrons which can be present in a subshell can be represented by
(a) 2l + 1
(b) 2n2
(c) 4l + 2
(d) 4l – 2
Answer: (c)
Explanation
Maximum number of electrons present in a subshell is given by the formula 4l+2, where l is the azimuthal quantum number. - The Schrodinger wave equation is
(a) Non linear differential equation
(b) linear differential equation
(c) 1st order equation
(d) All of these
Answer: (b)
Explanation
The Schrödinger equation is the equation of motion for nonrelativistic quantum mechanics. This equation is a linear partial differential equation and in simple situations can be solved using the technique of separation of variables. - In Sendmeyer, reaction, which of the following is not a Chlorinating agent?
(a) Thionyl Chloride
(b) Sulfuryl Chloride
(c) Phosphorus Chlorides
(d) None of the mentioned
Answer: (d)
Explanation
Thionyl Chloride (SOCl2), Sulfuryl Chloride (SO2Cl2) and Phosphorus Chlorides(PCl3, PCl5) are all used as chlorinating agents. - Which medium is used in the benzylic acid rearrangement reaction?
(a) Neutral
(b) Strong basic
(c) Mild acidic
(d) Strong acidic
Answer: (b)
Explanation
The attack of hydroxide on one of the carbonyl groups initiates the benzylic acid rearrangement process. - Gattermann reaction is given by:
(a) Benzene
(b) Toluene
(c) Cholorobenzene
(d) None of these
Answer: (a)
66-Which of the following will not undergo Friedel-Craft’s reaction readily?
(a) Toluene
(b) Xylene
(c) Cumene
(d) Nitrobenzene
Answer: (d)
Explanation
In nitrobenzene, the strong electron withdrawing nitro group deactivates the aromatic ring towards elctrophilic aromatic substitution by reducing the electron density.
Hence, nitro benzene will not undergo Friedal-Craft’s reaction easily.
67- Under which temperature, with a mild catalyst does toluene oxidize to benzaldehyde?
(a) High
(b) Moderate
(c) Low
(d) None of these
Answer: (b)
68- which of the following is the most activating in electrophilic aromatic substitution??
(a) -NH2
(b) -NO2
(c) -CN
(d) -NHCOCH3
Answer: (a)
- Which of the following is an application of thermodynamics?
(a) Refrigerators
(b) Gas compressors
(c) Power plants
(d) All of the mentioned
Answer: (d)
Explanation
The second law of thermodynamics applies to all refrigerators, deep freezers, industrial refrigeration systems, all forms of air-conditioning systems, heat pumps, and so on. Thermodynamic cycles govern the operation of all forms of air and gas compressors, blowers, and fans. The study of the feasibility of employing various forms of renewable energy sources for household and commercial purposes is an important topic area of thermodynamics. - What is the value of the absolute thermodynamic temperature scale?
(a) 3K
(b) 0K
(c) 1K
(d) 4K
Answer: (b)
Explanation
The temperature of an object on a scale with 0 as absolute zero is known as absolute temperature, also known as thermodynamic temperature. Kelvin and Rankine are absolute temperature scales. - Find the volume of O2 required to burn 1 L of propane completely, measured at 0℃ temperature and 1 atm pressure?
(a) 10 L
(b) 6 L
(c) 5 L
(d) 7 L
Answer: (c) - A gas X has Cp and Cv ratio as 1.4, at NTP 11.2 L of gas X will contain_______ number of atoms?
(a) 6.02 × 1023
(b) 1.2 × 1023
(c) 3.01 × 1023
(d) 2.01 × 1023
Answer: (a) - 6 gms of magnesium (atomic weight = 24), reacts with excess of an acid, the amount of H2 produced will be __ gm.?
(a) 0.5
(b) 1
(c) 3
(d) 5
Answer: (a) - The electronic spectra in the visible range span is __?
(a) 25000-72000 cm-1
(b) 12500-25000 cm-1
(c) 25000-50000 cm-1
(d) 15000-30000 cm-1
Answer: (b)
75.Arrange the various electronic transitions in the order of increasing energy.?
(a) n→σ* < π→π* < n→π* < σ→σ*
(b) n→σ* < n→π* < π→π* < σ→σ*
(c) n→π* < π→π* < n→σ* < σ→σ*
(d) σ→σ* < π→π* < n→π*
Answer: (c)
- Which of the following cannot show a vibrational absorption spectrum?
(a) OCS
(b) H2O
(c) CO2
(d) CH2 = C H2
Answer: (d)
77. Which one of the following compound forms salt on reaction with NaNH2?
(a) C2H2
(b) C2H6
(c) C6H6
(d) C2H4
Answer: (a)
Explanation
Acetylene on reaction with NaNH2, forms sodium salt.
The sp hybridized carbon atom in acetylene has higher electronegativity as compared to sp2 hybridized carbon atom in ethylene and sp3 hybridized carbon atom in ethane.
The carbon atom of C−H bond in acetylene attracts the shared electron pair towards itself to a greater extent and the hydrogen atom can be easily liberated as the proton.
Hence, the hydrogen atom attached to the triply bonded carbon atom in alkynes has appreciable acidic character.When acetylene reacts with NaNH2 which is the strong base reacts to form a sodium salt.
HC≡CH+NaNH2→HC≡C−Na+NaNH2→NaC≡CNa sodium acetylide disodium acetylide
78. Choose the process by which liquid hydrocarbons can be converted to gaseous hydrocarbons
(a) hydrolysis
(b) oxidation
(c) cracking
(d) distillation under reduced pressure
Answer: (c)
- Cooking gas is a Mixture of following two gases
(a) methane and ethane
(b) Ethane and Propane
(c) Propane and Butane
(d) Butane and Pentane
Answer: (c)
80.Which of following fuel has highest calorific value
(a) Methane
(b) Kerosene
(c) Hydrogen
(d) LPG
Answer: (c)
