Chemistry (School & UG)
Q. What is the main functional group in alkenes?
A.
Alcohol
B.
Aldehyde
C.
Alkene
D.
Alkyne
Show solution
Solution
The main functional group in alkenes is the alkene group, characterized by a carbon-carbon double bond.
Correct Answer: C — Alkene
Learn More →
Q. What is the main functional group present in acetic acid?
A.
Alcohol
B.
Aldehyde
C.
Carboxylic acid
D.
Ketone
Show solution
Solution
Acetic acid contains a carboxylic acid functional group, characterized by the -COOH group.
Correct Answer: C — Carboxylic acid
Learn More →
Q. What is the main functional group present in alkenes?
A.
Alcohol
B.
Aldehyde
C.
Alkene
D.
Alkyne
Show solution
Solution
The main functional group in alkenes is the alkene group, characterized by a carbon-carbon double bond.
Correct Answer: C — Alkene
Learn More →
Q. What is the main functional group present in amines?
A.
Hydroxyl group
B.
Carboxyl group
C.
Amino group
D.
Carbonyl group
Show solution
Solution
The main functional group present in amines is the amino group (-NH2).
Correct Answer: C — Amino group
Learn More →
Q. What is the main mechanism for the reaction of 1-bromobutane with sodium hydroxide in ethanol?
A.
SN1
B.
SN2
C.
E1
D.
E2
Show solution
Solution
The reaction of 1-bromobutane with sodium hydroxide in ethanol proceeds via the SN2 mechanism due to the primary nature of the substrate, allowing for a backside attack.
Correct Answer: B — SN2
Learn More →
Q. What is the main mechanism for the reaction of 1-bromopropane with sodium hydroxide in ethanol?
A.
SN1
B.
SN2
C.
E1
D.
E2
Show solution
Solution
The reaction of 1-bromopropane with sodium hydroxide in ethanol proceeds via the SN2 mechanism due to the primary nature of the substrate, allowing for a backside attack.
Correct Answer: B — SN2
Learn More →
Q. What is the main mechanism for the reaction of 2-bromobutane with sodium hydroxide in ethanol?
A.
SN1
B.
SN2
C.
E1
D.
E2
Show solution
Solution
The reaction proceeds via an SN2 mechanism due to the primary nature of the substrate and the strong nucleophile (OH-).
Correct Answer: B — SN2
Learn More →
Q. What is the main mechanism of the reaction between 1-bromopropane and sodium hydroxide in ethanol?
A.
SN1
B.
SN2
C.
E1
D.
E2
Show solution
Solution
The reaction between 1-bromopropane and sodium hydroxide in ethanol proceeds via the SN2 mechanism due to the primary nature of the alkyl halide, allowing for a direct nucleophilic attack.
Correct Answer: B — SN2
Learn More →
Q. What is the main mechanism of the reaction between an alkyl halide and a nucleophile in a bimolecular nucleophilic substitution (SN2) reaction?
A.
Formation of a carbocation
B.
Direct attack of the nucleophile
C.
Formation of a cyclic intermediate
D.
Elimination of a leaving group
Show solution
Solution
In an SN2 reaction, the nucleophile directly attacks the electrophilic carbon, leading to the simultaneous displacement of the leaving group.
Correct Answer: B — Direct attack of the nucleophile
Learn More →
Q. What is the main principle behind the use of UV-Vis spectroscopy in qualitative analysis?
A.
It measures the mass of a sample
B.
It detects the presence of specific ions based on their absorbance
C.
It separates components based on their charge
D.
It identifies compounds based on their melting points
Show solution
Solution
UV-Vis spectroscopy identifies compounds by measuring their absorbance at specific wavelengths, which correlates with the presence of certain ions.
Correct Answer: B — It detects the presence of specific ions based on their absorbance
Learn More →
Q. What is the main product of the dehydration of 2-butanol?
A.
Butene
B.
Butyne
C.
Butanol
D.
Butanal
Show solution
Solution
The dehydration of 2-butanol primarily produces butene through an elimination reaction.
Correct Answer: A — Butene
Learn More →
Q. What is the main product of the reaction between propene and bromine?
A.
1-bromopropane
B.
2-bromopropane
C.
1,2-dibromopropane
D.
Bromopropane
Show solution
Solution
The reaction of propene with bromine results in the formation of 1,2-dibromopropane due to the addition of bromine across the double bond.
Correct Answer: C — 1,2-dibromopropane
Learn More →
Q. What is the main product when an amine reacts with a carboxylic acid?
A.
Amide
B.
Ester
C.
Alcohol
D.
Aldehyde
Show solution
Solution
The main product of the reaction between an amine and a carboxylic acid is an amide.
Correct Answer: A — Amide
Learn More →
Q. What is the main product when hydrogen reacts with chlorine gas?
A.
Hydrochloric acid
B.
Hydrogen chloride
C.
Chlorine gas
D.
Chlorinated hydrocarbons
Show solution
Solution
When hydrogen reacts with chlorine gas, it forms hydrochloric acid (HCl) in aqueous solution.
Correct Answer: B — Hydrogen chloride
Learn More →
Q. What is the main product when hydrogen reacts with halogens?
A.
Hydrides
B.
Acids
C.
Salts
D.
Oxides
Show solution
Solution
When hydrogen reacts with halogens, the main product is hydrogen halides, which are acids.
Correct Answer: B — Acids
Learn More →
Q. What is the main purpose of calcination in metallurgy?
A.
To remove moisture
B.
To convert carbonates to oxides
C.
To reduce metal ores
D.
To purify metals
Show solution
Solution
Calcination is primarily used to convert carbonates to oxides by heating them in the absence of air.
Correct Answer: B — To convert carbonates to oxides
Learn More →
Q. What is the main purpose of roasting in metallurgy?
A.
To purify metals
B.
To convert sulfides to oxides
C.
To increase solubility
D.
To reduce metal ores
Show solution
Solution
Roasting is used to convert metal sulfides into oxides, making them easier to reduce.
Correct Answer: B — To convert sulfides to oxides
Learn More →
Q. What is the main purpose of using a buffer in electrophoresis?
A.
To increase the temperature
B.
To maintain a constant pH
C.
To enhance the conductivity
D.
To reduce sample size
Show solution
Solution
Buffers are used in electrophoresis to maintain a constant pH, which is crucial for the stability and migration of biomolecules.
Correct Answer: B — To maintain a constant pH
Learn More →
Q. What is the main purpose of using a buffer solution in titration?
A.
To increase the solubility of the titrant
B.
To maintain a constant pH during the reaction
C.
To enhance the color change of the indicator
D.
To reduce the volume of the solution
Show solution
Solution
A buffer solution is used in titration to maintain a constant pH during the reaction, ensuring accurate results.
Correct Answer: B — To maintain a constant pH during the reaction
Learn More →
Q. What is the main purpose of using a flux in metallurgy?
A.
To increase the melting point
B.
To facilitate the reduction of ores
C.
To remove impurities
D.
To enhance the color of metals
Show solution
Solution
Flux is used to remove impurities from ores during the smelting process, improving the quality of the extracted metal.
Correct Answer: C — To remove impurities
Learn More →
Q. What is the main purpose of using carbon in the extraction of metals from their ores?
A.
To increase melting point
B.
To act as a reducing agent
C.
To form alloys
D.
To enhance conductivity
Show solution
Solution
Carbon is used as a reducing agent in the extraction of metals, particularly in the smelting of iron.
Correct Answer: B — To act as a reducing agent
Learn More →
Q. What is the main purpose of using carbon in the extraction of metals from their oxides?
A.
To increase temperature
B.
To act as a catalyst
C.
To reduce metal oxides
D.
To form alloys
Show solution
Solution
Carbon is used to reduce metal oxides to their respective metals in a process known as reduction.
Correct Answer: C — To reduce metal oxides
Learn More →
Q. What is the main purpose of using carbon in the reduction of metal oxides?
A.
To increase temperature
B.
To act as a catalyst
C.
To provide electrons
D.
To form alloys
Show solution
Solution
Carbon acts as a reducing agent, providing electrons to reduce metal oxides to metals.
Correct Answer: C — To provide electrons
Learn More →
Q. What is the main reason for the difference in boiling points between cis and trans isomers?
A.
Molecular weight
B.
Dipole moment
C.
Hydrogen bonding
D.
Steric hindrance
Show solution
Solution
Cis isomers typically have a higher dipole moment due to their polar arrangement, leading to stronger intermolecular forces and higher boiling points.
Correct Answer: B — Dipole moment
Learn More →
Q. What is the main reason for the low boiling point of hydrogen compared to other group 1 hydrides?
A.
Hydrogen forms stronger bonds
B.
Hydrogen has a lower molecular weight
C.
Hydrogen does not form hydrogen bonds
D.
Hydrogen is a gas at room temperature
Show solution
Solution
Hydrogen does not form hydrogen bonds like heavier group 1 hydrides, leading to a lower boiling point.
Correct Answer: C — Hydrogen does not form hydrogen bonds
Learn More →
Q. What is the main use of alkenes in the industry?
A.
Fuel
B.
Plastics production
C.
Solvents
D.
Detergents
Show solution
Solution
Alkenes are primarily used in the production of plastics, such as polyethylene and polypropylene.
Correct Answer: B — Plastics production
Learn More →
Q. What is the major product of the addition of HBr to 2-pentene?
A.
1-bromopentane
B.
2-bromopentane
C.
3-bromopentane
D.
No reaction
Show solution
Solution
The addition of HBr follows Markovnikov's rule, leading to the formation of 2-bromopentane as the major product.
Correct Answer: B — 2-bromopentane
Learn More →
Q. What is the major product of the dehydration of 2-butanol?
A.
Butene
B.
Butyne
C.
Butanol
D.
Butanal
Show solution
Solution
The dehydration of 2-butanol typically yields butene as the major product through an elimination reaction.
Correct Answer: A — Butene
Learn More →
Q. What is the major product of the electrophilic substitution of benzene with bromine in the presence of FeBr3?
A.
Bromobenzene
B.
Benzyl bromide
C.
Bromobenzyl
D.
Benzene
Show solution
Solution
The major product is bromobenzene, formed when bromine reacts with benzene in the presence of a Lewis acid catalyst like FeBr3.
Correct Answer: A — Bromobenzene
Learn More →
Q. What is the major product of the electrophilic substitution of toluene with bromine in the presence of FeBr3?
A.
Bromotoluene
B.
Bromobenzene
C.
Benzyl bromide
D.
No reaction
Show solution
Solution
Toluene is more reactive than benzene due to the electron-donating methyl group, leading to bromotoluene as the major product.
Correct Answer: A — Bromotoluene
Learn More →
Showing 751 to 780 of 1878 (63 Pages)