Class 11th

If the equation a|z|² + α'z + αz' + d = 0 represents a circle where a, d are real constants, then which of the following condition is correct?

The common positive oxidation states for an element with atomic number 24, are:

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: During the boiling of water having temporary hardness, Mg(HCO?)? is converted to MgCO?.
Reason R: The solubility product of Mg(OH)? is greater than that of MgCO?. In the light of the above statements, choose the most appropriate answer from the options given below:

Considering the below reaction, X and Y respectively are

Match List - I with List - II:
List - I (Process)
(a) Deacon's process
(b) Contact process
(c) Cracking of hydrocarbons
(d) Hydrogenation of vegetable oils

List - II (Catalyst)
(i) ZSM-5
(ii) CuCl?
(iii) Particles 'Ni'
(iv) V?O?

Choose the most appropriate answer from the options given below

Match List - I with List - II:
List - I (Class of Drug)
(a) Antacid
(b) Artificial Sweetener
(c) Antifertility
(d) Tranquilizers

List - II (Example)
(i) Novestrol
(ii) Cimetidine
(iii) Valium
(iv) Alitame

Choose the most appropriate match.

Which of the following statement(s) is (are) incorrect reason for eutrophication?
(A) Excess usage of fertilisers
(B) Excess usage of detergents
(C) Dense plant population in water bodies
(D) Lack of nutrients in water bodies that prevent plant growth
Choose the most appropriate answer from the options given below:

The set that represents the pair of neutral oxides of nitrogen is:

The functional groups that are responsible for the ion-exchange property of cation and anion exchange resins, respectively, are:

A particle performs simple harmonic motion with a period of 2 second. The time taken by the particle to cover a displacement equal to half of its amplitude from the mean position is 1/a s. The value of 'a' to the nearest integer is-----------.