CBSE 11TH CHEMISTRY - Online Test

Answer : Option B
Explaination / Solution:

Metal hydrides (MHx) are the most technologically relevant class of hydrogen storage materials because they can be used in a range of applications including neutron moderation,electrochemical cycling, thermal storage, heat pumps, and purification/separation.

The metal hydrides such as intermetallic alloys and solid solutions have interstitial vacancies where atomic hydrogen is absorbed via an exothermic reaction; however, by endothermic path, the metal hydride desorbs the hydrogen reversibly at ambient to moderate temperatures.

Answer : Option A
Explaination / Solution:

overlapping of atomic orbitals having electrons of opposite spin take palce in the formation of molecule.

Answer : Option B
Explaination / Solution:

II is very stable because +ve charge is dispersed by +R effect of −−OCH3group. I will be more stable than III because of more hyperconjugation.

Answer : Option C
Explaination / Solution:

K has +1 oxidation state. "The potassium atom losses one electron when forming compound as it has one electron on it's valence shell".

Answer : Option A
Explaination / Solution:

Z=PV/nRT, is a correction factor which describe the deviation of real gas from ideal gas behaviour. it is defined as the ratio of the molar volume of a gas to the molar volume of an ideal gas at the same temperature and pressure.

Answer : Option C
Explaination / Solution:

Reaction Quoitennt (Q) =K ( equilibrium) Q>K (backward Reaction) Q

Answer : Option C
Explaination / Solution:

Elimination reaction is a type of  organic reaction in which two  substituents are removed from a molecule in either one or two steps .When the starting dihalide is a vicinal dihalide , alkyne is obtained by two successive elimination reactions. 

Example :

Vicinal dihalide,(CH2Br−CH2Br) on treatment withalcoholicKOH forms a monosubstituted alkene Vinyl bromideCH2CHBrwhich when reacted with sodium amide ,  NaNH2 forms ethyne  (ie. an alkyne ). The steps of conversion are ,

Answer : Option B
Explaination / Solution:

This is redox couple.

Where following reaction take place :

Zn2+  + 2e-  → Zn

Answer : Option A
Explaination / Solution:

The lattice enthalpy of an ionic compound is the enthalpy change which occurs when one mole of an ionic compound dissociates into its ions in gaseous state.

Answer : Option B
Explaination / Solution:

d-Block elements also known as transition elements are characterized by the filling of inner d orbitals by electrons before the valence-shell s orbital.