PUC Science 2nd PUC Class 12 - Karnataka Board PUC Question Bank Solutions for Chemistry

Differentiate between adsorbtion and absorption.

Give reasons:

Transition metals show variable oxidation states.

Write the name of two monosaccharides obtained on hydrolysis of lactose sugar.

What is the formula of a compound in which the element Y forms ccp lattice and atoms of X occupy 1/3^rd of tetrahedral voids?

What are the transition elements? Write two characteristics of the transition elements.

How would you account for the following : Transition metals form coloured compounds

Write the product obtained when D-glucose reacts with H₂N − OH.

Define the following term: Primitive unit cells

Account for the following:

Cu⁺ ion is unstable in aqueous solution.

From the given data of E⁰ values, answer the following questions :

(1) Why is `E_(((Cu^(2+))/(Cu)))` value exceptionally positive

(2) Why is `E_(((Mn^(2+))/(Mn)))` value is highly negative as compared to other elements

(3) Which is the stronger reducing agents Cr²⁺ or Fe²⁺ ? Give Reason.

What is the effect of temperature on chemisorption ?

How will you distinguish between the following pair of terms?

Crystal lattice and unit cell

Account for the following:

Zn is not considered as a transition element.

Account for the following:

E° value for the Mn³⁺/Mn²⁺ couple is much more positive than that for Cr³⁺/Cr²⁺.

Out of Mn³⁺ and Cr³⁺, which is more paramagnetic and why ?

(Atomic nos. : Mn = 25, Cr = 24)

Why is adsorption always exothermic?

Why does NO₂ dimerise?

Give the significance of a ‘lattice point’.

Name the parameters that characterize a unit cell.

Which of the following lattices has the highest packing efficiency (i) simple cubic (ii) body-centred cubic and (iii) hexagonal close-packed lattice?