Ncert Solutions Chemistry Class 12th

In the given reaction

Amongst the following, the major product of the given chemical reaction is

During halogens test, sodium fusion extract is boiled with concentrated HNO₃ to

Given below are two statements: one is labeled as Assertion A  and the other is labeled as Reason R.

Assertion A:  A mixture contains benzoic acid  and naphthalene. THE pure benzoic acid can be separated out by the use of benzene.

Reason R: Benzoic acid is soluble in hot water.

In the light of the above statements, choose the most appropriate answer form the options given below:

Given below are two statements: one is labeled as Assertion A  and the other is labeled as Reason R.

Assertion A: Polluted water may have a value of BOD of the order of 17 ppm.

Reason R: BOD is a measure of oxygen required to oxidize both the biodegradable and non-biodegradable organic material in water

In the light of the above statements, choose the most appropriate answer from the options given below.

The number of bridged oxygen atoms present in compound B formed form the following reaction is   $Pb{\left(N{O}_3\right)}_2\stackrel{673K}{\to }A+PbO+O_2$

$A\stackrel{Dimerise}{\to }B$

Given below are two statements.

Statement I: During electrolytic refining, blister copper deposits precious metals.

Statement II: In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.

In the light of the above statements, choose the correct answer form the option given below:

The Ksp for bismuth sulphide (Bi₂S₃) is 1.08 * 10^-73. The solubility of Bi₂S₃ in mol L^-1 at 298 K is

The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is:    

[Given: The threshold frequency of platinum is 1.3 * 10¹⁵s^-1 and h = 6.6 * 10^-34 J s.]

Given below are two statements:

Statement I: On heating with KHSO₄, glycerol is dehydrated and acrolein is formed.

Statement II:  Acrolein has fruity odour and can be used to test glycerol's presence.                  

Choose the correct option.