HSC Science (Computer Science) इयत्ता १२ वी - Maharashtra State Board Question Bank Solutions for Chemistry

What type of semiconductor is obtained when silicon is doped with boron? 

To prepare n-type semiconductor the impurity to be added to silicon should have the following number of valence electrons:

(a) 2

(b) 3

(c) 4

(d) 5

When a hole is produced in P-type semiconductor, there is _______.

What is ‘effective atomic number’ (EAN)?

Calculate the effective atomic number of the central metal atom in the following  compounds:

K₄Fe(CN)₆  Fe(Z=26)

Effective atomic number rule is used to find _______.
(A) geometry of complex
(B) stability of complex
(C) number of isomers of complex
(D) number of possible ligands around metal ion in complex

Write applications of standard molar entropy°.

Calculate EAN of cobalt (Z=27) in [CO(NH₃)₆]⁺³ and of zinc (Z=30) in [Zn(NH₃)₄]SO₄.

Calculate the effective atomic number of the central metal atom in the following  compounds:

Cr(CO)₆ Cr(Z=24)

A pure semiconductor is ________.

(a) an extrinsic semiconductor

(b) an intrinsic semiconductor

(c) p-type semiconductor

(d) n-type semiconductor

Distinguish between p-type and n-type semiconductors.

What is the ratio of octahedral holes to the number of anions in hexagonal closed packed structure?

A substance which shows the highest entropy is ___________.

What is the action of lithium aluminum hydride in the presence of ether on the following compounds? 
a. Nitroethane 
b. 2-Methyl-1-nitropropane

What are the stable oxidation states of plutonium, cerium, manganese, Europium?

Answer the following

Why nobelium is the only actinoid with a +2 oxidation state?

Answer the following

Explain with the help of a balanced chemical equation, why the solution of Ce(IV) is acidic.

Answer the following

What is meant by ‘shielding of electrons’ in an atom?

Answer the following

The atomic number of an element is 90. Is this element diamagnetic or paramagnetic?

Answer the following

What is meant by diamagnetic and paramagnetic? Give one example of diamagnetic and paramagnetic transition metal and lanthanoid metal.