Chemistry - Online Test
Q1. The state of hybridization of the central atom and the number of lone pairs over the central atom in are
Answer : Option C
Explaination / Solution:
CN= 0.5[V+M-C+A]
For POCl3 V=5 M=3 C =A=0 So CN=4
so hybridization is sp3. And there are 4 bps so 0 lps.
Q2. Carbon tetra chloride has a dipole moment
Answer : Option B
Explaination / Solution:
CCl4 is symmetrical hence dipole moment is zeo.
Q3. Choose the correct order of decrease in hydration enthalpies of alkaline earth metals in the options given below
Answer : Option C
Explaination / Solution:
As the size increases due to increase in ionic radii , hydration energy decreases.
Q4. When an organic compound is present in an aqueous medium, it is separated by
Answer : Option A
Explaination / Solution:
They are separated by differential extraction.
Q5. For the first order reaction, half life is equal to
Answer : Option D
Explaination / Solution:
For 1st order reaction half life is independent of initial concentration of reactant.
Q6. Liquid – liquid solutions are known as
Answer : Option D
Explaination / Solution:
Dispersed phase and dispersion medium both are liquids.
Q7. Calculate the volume occupied by 8.8 g of CO2 at 31.1 and 1 bar pressure. R = 0.083 bar .
Answer : Option B
Explaination / Solution:
V=wRTMPV=8.8×0.083×304.144×1=5.05L
Q8. Two nucleic acid chains are wound about each other and held together by hydrogen bonds between pairs of bases is called
Answer : Option D
Explaination / Solution:
Secondary structures are hydrogen pairs of bases.
Q9. Which of the following compounds will react with sodium hydroxide solution in water?
Answer : Option B
Explaination / Solution:
Phenol is more soluble in NaOH than in water is because phenol is slightly more acidic than alcohols. The Ka for phenol in water is 1e-10 which is not very strong. But by mixing with NaOH, it causes the phenol to release the H+ to form sodium phenoxide.
Q10. Which of the following has highest boiling point?
Answer : Option A
Explaination / Solution:
i=3 so ΔTb will be maximum and hence Tb will be maximum.
