CBSE 12TH CHEMISTRY - Online Test
Q1. insulin is a protein which contains _______ amino acids
Answer : Option B
Explaination / Solution:
Insulin contain 51 amino acids
Q2. Alcohols are easily dehydrated in the following order
Answer : Option B
Explaination / Solution:
The rate of dehydration is related to the ease of formation of Carbocation and the energy of the carbocation intermediate. -.
Dehydration involves formation of carbocation 1st and since tertiary carbocation is more stable than secondary and primary therefore 3° is dehydrated first.
The ease of formation of Carbocation is Tertiary>Secondary>Primary.
Q3. In the depression of freezing point experiment, it is found that
Answer : Option C
Explaination / Solution:
Addition of non volatile solute decreases the vapour pressure.
Q4. Which one of the following is used as an anaesthetic in dentistry
Answer : Option A
Explaination / Solution:
Novocaine (or novocain), also known as procaine hydrochloride, is a local anesthetic that is commonly used during dental procedures, like cavity fillings.
Q5. Some polymers are called thermoplastic polymers because
Answer : Option C
Explaination / Solution:
Thermoplastic polymer get soften on heating and gets harden on cooling.
Q6. Fluorine reacts with H2S to produce
Answer : Option C
Explaination / Solution:
3F2+ H2S→SF4+ 2HF
Q7. Liquation method is used for the metals which have
Answer : Option D
Explaination / Solution:
Liquification is purification technique used for metals having low melting points.
Q8. Zr and Hf have almost equal atomic and ionic radii because
Answer : Option A
Explaination / Solution:
Due to presence of Lanthanide series in which electron enter f orbital which have poor shielding effect size of 5d series and 4d series doesnot change much . this is known as lanthanide contraction.
Q9. Arrange the following compounds in decreasing order of their acid strength: i) trichloroacetic acid ii) trifluoroacetic acid iii) acetic acid and iv)formic acid
Answer : Option B
Explaination / Solution:
Fluorine is most electronegative so it increases acidity.
Q10. Salvarsan has
Answer : Option C
Explaination / Solution:
It has -As=As- linkage.
