CBSE 12TH CHEMISTRY - Online Test
Q1. Repeated addition of monomer molecule possessing double or triple bonds, in this case, propene, forms
Answer : Option C
Explaination / Solution:
This will form Polypropene.
Q2. In laboratory ammonia is prepared by heating
Answer : Option D
Explaination / Solution:
Q3. Which metal is also found in sea beds ?
Answer : Option C
Explaination / Solution:
Manganese is found in sea beds.
Q4. Which among the following transition metal has lowest melting point?
Answer : Option B
Explaination / Solution:
Zn has lowest melting point because it doesnot have any unpaired electrons.
Q5. The carbonyl carbon atom
Answer : Option C
Explaination / Solution:
R1R2C=O is carbonyl so 3 sigma bond and 1 pie bond.
Q6. Which of the following is most likely structure of CrCl3.6H2O if 1/3 of total chlorine of the compound is precipitated by adding AgNO3 to its aqueous solution?
Answer : Option C
Explaination / Solution:
1 mol of Cl is precipitated so 1 Cl will be present outside the coordination sphere.
Q7. Very low concentrations of Sulphur – dioxide acts as
Answer : Option A
Explaination / Solution:
Very low concentration of act as only disinfectant.
Q8. For a general electrochemical reaction of the type :
Nernst equation can be written as:
Nernst equation can be written as:
Answer : Option D
Explaination / Solution:
Q9. AgCN reacts with haloalkanes to form isocyanide. Haloalkanes react with KCN to form alkyl cyanides as main product
Answer : Option B
Explaination / Solution:
AgCN is covalent in nature while KCN is ionic so KCN produces CN- in the solution.
CN- is an ambient nucleophile i.e. it can form bond from both C and N atoms. KCN is an ionic compound so both C and N sides are available for the formation of bond, but C-C bond is stronger than C-N bond so cynide is formed. AgCN is a covalent compound so only N side is available for CN to form bond and thus isocynide is formed
Q10. The most abundant organic compound on earth
Answer : Option A
Explaination / Solution:
Glucose is most abundant organic compound on earth.
