Science (English Medium) Class 12 - CBSE Question Bank Solutions for Chemistry

Why is Butan-1-ol optically inactive but Butan-2-ol is optically active?

Draw the geometrical isomers of complex [Pt(en)₂Cl₂]²⁺.

What is the role of dilute NaCN in the extraction of gold ?

Illustrate the following reactions giving suitable example in each case 

Ammonolysis

Write the structures of main products when benzene diazonium chloride (C6 H5 N+2CI−)C6 H5 N2+CI- reacts with the  :  HBF₄/∆

 Write the structures of main products when benzene diazonium chloride (C6 H5 N+2CI−)C6 H5 N2+CI- reacts with the :Cu/HBr

Which reducing agent is employed to get copper from the leached low-grade copper ore?

Glucose on reaction with HI gives n-hexane. What does it suggest about the structure of glucose?

State Henry's Law. What is the effect of temperature on the solubility of a gas in a liquid?

Arrange the following in increasing order of basic strength :

C₆H₅NH₂, C₆H₅NHCH₃, C₆H₅N(CH₃)₂

What happens when Phenol is oxidised with Na₂Cr₂O₇/H⁺?

Differentiable between the following: 
Amylose and Amylopectin 

Define order of reaction. How does order of a reaction differ from molecularity for a complex reaction? 

 A first order reaction is 50% complete in 25 minutes. Calculate the time for 80% completion of the reaction.

Give a simple chemical test to distinguish between 
 

Write the main product formed when propanal reacts with the following reagents: 
2 moles of 3 CH OH in presence of dry HCl 

Write the main product formed when propanal reacts with the following reagents: 
H₂N- NH₂  followed by heating with KOH in ethylene glycol.

 Acetone, Acetaldehyde, Benzaldehyde, Acetophenone – reactivity towards addition of HCN. 

Answer the following question.
What is the basic structural difference between glucose and fructose?

Write the name of gas released when Cu is added to dilute HNO₃