CBSE 11TH CHEMISTRY - Online Test

Answer : Option D
Explaination / Solution:

Total number of electrons in N2 molecule is 7+ 7= 14.

As per the formula Bonded pair of electrons Nb: σ1s2 σ2s2 π2p2y π2p2z σ2p2x

Total 10 electrons.

Anti bond pairs of electrons Na: σ1s∗2 σ2s∗2Total 4 electrons.
Bond Order (B.O.) = Nb−Na2=10−42=3

Similarly bond order of CO And NO+ is 3

Answer : Option C
Explaination / Solution:

they are aromatic system as they have benzene ring intact.

Answer : Option D
Explaination / Solution:

The question is based on the statement of Dalton Law of Partial pressures for Gases which states that total pressure exerted by mixture of non reacting gases is equal to the sum of partialpressure of individual gases.

Answer : Option C
Explaination / Solution:

For dissolution of gases in liquids, the concentration of a gas in liquid is proportional to the pressure of the gas over the liquid

Answer : Option C
Explaination / Solution:

As surface area decreases with branching,the boiling point also decreases.

Answer : Option B
Explaination / Solution:

Reducing agent is one in which element undergo oxidation itself and make the other substance reduce.

Answer : Option C
Explaination / Solution:

Hess’s Law states that the sum of the standard enthalpies of the intermediate reactions into which the overall reaction may be divided at the same temperature.

Answer : Option C
Explaination / Solution:

The electronic configuration of scandium is [Ar] 3d1 4s2.

Answer : Option C
Explaination / Solution:

The effect of Heisenberg uncertainty principle is significant only for motion of microscopic objects, it is negligible in case of macroscopic objects. For example, we apply the concept of uncertainty to an object of mass 1 milligram.

Δx×Δvx=h4πm

=6.626×10−344×3.1416×10−6≈10−28m2s−1

The value of ΔxΔvxis very small and insignificant in this case. Therefore, when we deal with heavier objects the associated uncertainties have no real consequences and can be neglected.

Answer : Option B
Explaination / Solution:

Avagadro's constant  represents the number of  entities ( viz, atoms , molecules or ions )  present  in 1 mole of a substance .

The  constant ( denoted by  N )

 =6.022 x 1023