12th Standard CBSE Syllabus & Materials
12th Standard CBSE
CBSE 12th Economics Government Budget and the Economy Previous year Question Papers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Computer Science Interface Python with MySQL - New Previous year Question Papers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Computer Science Database Concept - New Previous year Question Papers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Computer Science Data Communication - New Previous year Question Papers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Computer Science Data Structures - New Previous year Question Papers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Computer Science Functions - New Previous year Question Papers Study Material - QB365 Set A
Published on: 25/05/2021
QB365 Provides the updated NCERT Exemplar Questions for Class 12, and also provide the detail solution for each and every case study questions. NCERT Exemplar questions are latest updated question pattern from NCERT, QB365 will helps to get more marks in Exams
Download CBSE Class 12th Standard CBSE Chemistry question papers, sample papers, important questions, and previous year solved papers in PDF format. Get free study materials, NCERT solutions, and exam preparation resources for Class 12th Standard CBSE Chemistry
Questions + Answers key
Take MCQ Chemistry Test
1.
Which of the following is/are not known ? PCl3, AsCl3, SbCl3, NCl5, BiCl5.
2.
Which is a stronger reducing agent, SbH3 or BiH3, and why?
3.
Which is least basic ? SbH3, PH3, NH3, ASH3 ?
4.
Which is least acidic ? SbH3, Ph3, NH3,AsH3
5.
Give reasons for the least rectivity of nitrogen molecule.
1.
( )
(i) NCl5 (due to absence of d-orbitals)
(ii) BiCl5 (Bi5+ being an oxidising agent oxidises Cl- ion to Cl2 and Cl-ion being a reducing agent reduces Bi5+ to Bi 3+).
2.
( )
As we move down the group 15 elements from Sb to Bi, the atomic size increase and hence the strength of the bond it makes with hydrogen decreases, i.e., Bi-H bond is weaker than Sb-H bond. In other words, BiH3 is thermally less stable than sbH3. Therefore, on heating, BiH3 has a greater tendency to liberate hydrogen than SbH3 is a stronger reducing agent than SbH3.
3.
( )
A compound which is most acidic is obviously least basic. Since SbH3 is most acidic, therefore, it is least basic. or As the size of the atom increases, electron density decreases and hence basicity decreases. Thus SbH3 is least basic.
4.
( )
A compound which is most basic is obviously least acidic. Since NH3 is the most basic compound, therefore, it is least acidic.
5.
( )
Due to presence of a triple bond between the two N-atoms, the bond dissociation enthalpy (941.4 kJ mol-1) is very high. Hence, N2 is least reactive.
12th Standard CBSE Syllabus & Materials
12th Standard CBSE
CBSE 12th Computer Science Python Revision Tour I - New Previous year Question Papers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Business Studies Planning Important Questions And Answers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Business Studies Business Environment Important Questions And Answers Study Material - QB365 Set A
NEW12th Standard CBSE
CBSE 12th Business Studies Principles of Management Important Questions And Answers Study Material - QB365 Set A
NCERT Books
Syllabus
Exam Pattern
Sample Question Papers
Previous year Question Papers
Important Notes
MCQ Practice test
NCERT Exemplers
Case study Questions
Image Based Questions
Passage based Questions
HOT Questions
Value Based Questions
Model Questions Papers
NCERT ( Book Back ) Questions
Assertion and Reason
Important Questions And Answers
CBSE 12th Standard CBSE Subjects
CBSE Standards
