English

Science (English Medium) Class 12 - CBSE Important Questions

Advertisements
[object Object]
[object Object]
Subjects
Popular subjects
Topics

Please select a subject first

Advertisements
Advertisements
< prev  21 to 40 of 6447  next > 

Draw the structures of the HClO3.

Appears in 10 question papers
Chapter: [7] P - Block Elements
Concept: P - Block Group 17 Elements >> Oxoacids of Halogens

Write the chemical equations to illustrate the following name reaction: 

Cannizzaro’s reaction

Appears in 10 question papers
Chapter: [8] Aldehydes, Ketones and Carboxylic Acids
Concept: Aldehydes and Ketones >> Chemical Reactions of Aldehydes and Ketones - Other Reactions

Give reasons for the following:

Aniline does not undergo Friedel- Crafts reaction.

Appears in 10 question papers
Chapter: [9] Amines
Concept: Amines >> Chemical Reactions of Amines - Electrophilic Substitution

Why is bithional added to soap?

Appears in 10 question papers
Chapter: [16] Chemistry in Everyday Life
Concept: Cleansing Agents - Soaps

State the two Kirchhoff’s rules used in electric networks. How are there rules justified?

Appears in 10 question papers
Chapter: [3] Current Electricity
Concept: Kirchhoff’s Laws

In a single slit diffraction experiment, the width of the slit is made double the original width. How does this affect the size and intensity of the central diffraction band?

Appears in 10 question papers
Chapter: [10] Wave Optics
Concept: Diffraction of Light >> The Single Slit

Give the truth table and circuit symbol for NAND gate

Appears in 10 question papers
Chapter: [14] Semiconductor Electronics - Materials, Devices and Simple Circuits
Concept: Digital Electronics and Logic Gates

Calculate the freezing point of a solution containing 60 g of glucose (Molar mass = 180 g mol–1) in 250 g of water. (Kf of water = 1.86 K kg mol–1)

Appears in 9 question papers
Chapter: [1] Solutions
Concept: Colligative Properties and Determination of Molar Mass >> Depression of Freezing Point

Give reasons for the following:

Measurement of osmotic pressure method is preferred for the determination of molar masses of macromolecules such as proteins and polymers.

Appears in 9 question papers
Chapter: [1] Solutions
Concept: Colligative Properties and Determination of Molar Mass >> Depression of Freezing Point

Give reasons for the following :

Aquatic animals are more comfortable in the cold water than in warm water.

Appears in 9 question papers
Chapter: [1] Solutions
Concept: Solubility >> Solubility of a Gas in a Liquid

Give reasons for the following

Elevation of the boiling point of 1 M KCl solution is nearly double than that of 1 M sugar solution.

Appears in 9 question papers
Chapter: [1] Solutions
Concept: Abnormal Molar Masses

An element 'X' (At. mass = 40 g mol-1) having f.c.c. the structure has unit cell edge length of 400 pm. Calculate the density of 'X' and the number of unit cells in 4 g of 'X'. (NA = 6.022 × 1023 mol-1)

Appears in 9 question papers
Chapter: [1] Solid State
Concept: Number of Atoms in a Unit Cell

For the reaction

`2AgCl (s) + H_2 (g) ("1 atm") -> 2Ag (s) + 2H^(+)  (0.1 M) +  2Cl^(-) (0.1 M)`

`triangleG^0 = -43600 J at 25^@ C`

Calculate the e.m.f. of the cell

`[log 10^(-n) = -n]` 

Appears in 9 question papers
Chapter: [2] Electrochemistry
Concept: Relation Between Gibbs Energy Change and Emf of a Cell

Write two advantages of fuel cell

Appears in 9 question papers
Chapter: [2] Electrochemistry
Concept: Fuel Cells

An analysis shows that FeO has a non-stoichiometric composition with formula Fe0.95O. Give reason.

Appears in 9 question papers
Chapter: [4] d-block and f-block Elements
Concept: General Properties of the Transition Elements (D-block)

Complete and balance the following chemical equations

`Fe^(2+) + MnO_4^(-) + H^+ ->`

Appears in 9 question papers
Chapter: [4] d-block and f-block Elements
Concept: General Properties of the Transition Elements (D-block)

Complete and balance the following chemical equations

`MnO_4^(-) + H_2O + I^(-) ->`

Appears in 9 question papers
Chapter: [4] d-block and f-block Elements
Concept: General Properties of the Transition Elements (D-block)

Give reasons: 

E° value for the Mn3+/Mn2+ couple is much more positive than that for Fe3+/Fe2+.

Appears in 9 question papers
Chapter: [4] d-block and f-block Elements
Concept: General Properties of the Transition Elements (D-block)

Give reasons Iron has the higher enthalpy of atomization than that of copper.

Appears in 9 question papers
Chapter: [4] d-block and f-block Elements
Concept: General Properties of the Transition Elements (D-block)

Give reasons: Sc3+ is colourless in aqueous solution whereas Ti3+ is coloured.

Appears in 9 question papers
Chapter: [4] d-block and f-block Elements
Concept: General Properties of the Transition Elements (D-block)
< prev  21 to 40 of 6447  next > 
Advertisements
Advertisements
CBSE Science (English Medium) Class 12 Important Questions
Important Questions for CBSE Science (English Medium) Class 12 Biology
Important Questions for CBSE Science (English Medium) Class 12 Chemistry
Important Questions for CBSE Science (English Medium) Class 12 Computer Science (C++)
Important Questions for CBSE Science (English Medium) Class 12 Computer Science (Python)
Important Questions for CBSE Science (English Medium) Class 12 English Core
Important Questions for CBSE Science (English Medium) Class 12 English Elective - NCERT
Important Questions for CBSE Science (English Medium) Class 12 Entrepreneurship
Important Questions for CBSE Science (English Medium) Class 12 Geography
Important Questions for CBSE Science (English Medium) Class 12 Hindi (Core)
Important Questions for CBSE Science (English Medium) Class 12 Hindi (Elective)
Important Questions for CBSE Science (English Medium) Class 12 History
Important Questions for CBSE Science (English Medium) Class 12 Informatics Practices
Important Questions for CBSE Science (English Medium) Class 12 Mathematics
Important Questions for CBSE Science (English Medium) Class 12 Physical Education
Important Questions for CBSE Science (English Medium) Class 12 Physics
Important Questions for CBSE Science (English Medium) Class 12 Political Science
Important Questions for CBSE Science (English Medium) Class 12 Psychology
Important Questions for CBSE Science (English Medium) Class 12 Sanskrit (Core)
Important Questions for CBSE Science (English Medium) Class 12 Sociology
Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×