CBSE 12TH CHEMISTRY - Online Test
Q1. Lather formed in shaving soaps is due to
Answer : Option A
Explaination / Solution:
Lather forms in shaving soaps is due to Sodium rosinate.
Q2. The IUPAC name [CoCl(NO2)(en)2]Cl is
Answer : Option A
Explaination / Solution:
Name of ligands name first in alphabetical order followed by anme of central ion.
Q3. Molar conductivity denoted by the symbol Λm is related to the conductivity of the solution by the equation (κis the conductivity and c the concentration)
Answer : Option C
Explaination / Solution:
Molar conductivity is specific conductivity of a solution having 1 mole of electrolyte dissolved per litre of solution.
Q4. CH3 = CH2 CH3 + H – I → CH3 CH2 CH2I + CH3 CHICH3 (major) This reaction is
Answer : Option D
Explaination / Solution:
This is electrophilic addition reaction following Markovnikoffs rule.and negative part that is I will go to the carbon having lesser number of hydrogen.
Q5. Acetylation of glucose yields
Answer : Option D
Explaination / Solution:
Acetyl group adds in glucose, giving acetylation reaction.
Q6. For the first order reaction, half life is equal to
Answer : Option C
Explaination / Solution:
For 1st order reaction half life is independent of initial concentration of reactant.
Q7. Hardening of leather in tanning industry is based on
Answer : Option A
Explaination / Solution:
Fact
Q8. Ketones react with Grignard reagent to produce
Answer : Option B
Explaination / Solution:
The Grignard Reaction is the addition of an organomagnesium halide (Grignard reagent) to a ketone or aldehyde, to form a tertiary or secondary alcohol, respectively. The reaction with formaldehyde leads to a primary alcohol.
Grignard Reagents are also used in the following important reactions: The addition of an excess of a Grignard reagent to an ester or lactone gives a tertiary alcohol in which two alkyl groups are the same, and the addition of a Grignard reagent to a nitrile produces an unsymmetrical ketone via a metalloimine intermediate.
Q9. The main product formed by treating an alkyl or benzyl halide with excess ammonia
Answer : Option B
Explaination / Solution:
The major product is primary amine.
Q10. Cryoscopic constant of a liquid is
Answer : Option C
Explaination / Solution:
ΔTf= Kfm. When m(molality )= 1m then kf= ΔTf
