PUC Science 2nd PUC Class 12 - Karnataka Board PUC Important Questions

Write the structures of the following molecule: 

H₂SO₃

Give reasons for the following : H₂Te is the strongest reducing agent amongst all the hydrides of Group 16 elements.

Give reasons for the following : Phenol is more acidic than ethanol.

Give reasons for the following : Boiling point of ethanol is higher in comparison to methoxymethane.

Write the structures of the main products when acetone (CH₃ − CO − CH₃) reacts with the following reagents :

CH₃MgBr and then H₃O⁺

Draw the structures of the following:
(1) HClO₄
(2) H₃PO₃

Complete the following equation: 

\[\ce{XeF2 + H2O ->}\]

Give a simple chemical test to distinguish between the following pair of compounds:

Ethanal and Propanal

A compound 'A' of molecular formula C₂H₃OCl undergoes a series of reactions as shown below. Write the structures of A, B, C and D in the following reactions :

Distinguish between the following : Benzoic acid and methyl benzoate

Write the structure of 2-methylbutanal.

Write the structures of the main products when acetone (CH₃ − CO − CH₃) reacts with the following reagent :

Zn − Hg/conc. HCl

Write the structures of the main products when acetone (CH₃ − CO − CH₃) reacts with the following reagent :

H₂N − NHCONH₂/H⁺

Arrange the following in the increasing order of their boiling points : C₂H₅OH, CH₃ − CHO, CH₃ − COOH

Give a simple chemical test to distinguish between the following pair of compounds :

CH₃CH₂CHO and CH₃CH₂COCH₃

How will you bring about the following conversion?

Benzoyl chloride to benzaldehyde.

Describe the following:

Cannizzaro reaction

Complete the synthesis by giving missing starting material, reagent or product.

Arrange the following in increasing order of their basic strength in aqueous solution:

\[\ce{CH3NH2, (CH3)3N, (CH3)2NH}\]

Arrange the following in increasing order of their basic strength :

C₆H₅ – NH₂, C₆H₅ – CH₂ – NH₂, C₆H₅ – NH – CH₃