Classification of Elements and Periodicity in Properties

Number of elements from the following that CANNOT form compounds with valencies which match with their respective group valencies is . B, C, N, S, O, F, P, Al, Si

1. 7
2. 3
3. 5
4. 6

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

1. Statement I is true but Statement II is false
2. Both Statement I and Statement II are false
3. Statement I is false but Statement II is true
4. Both Statement I and Statement II are true

In case of isoelectronic species the size of F-, Ne and Na+ is affected by :

1. Nuclear charge (Z)
2. None of the factors because their size is the same
3. Electron-electron interaction in the outer orbitals
4. Principal quantum number (n)

Among the following oxides of p-block elements, number of oxides having amphoteric nature is . Cl2O7, CO, PbO2, N2O, NO, Al2O3, SiO2, N2O5, SnO2

Given below are two statements : In the light of the above statements, choose the most appropriate answer from the options given below :

1. Both Statement I and Statement II are false
2. Both Statement I and Statement II are true
3. Statement I is false but Statement II is true
4. Statement I is true but Statement II is false

The correct sequence of electron gain enthalpy of the elements listed below is Choose the most appropriate from the options given below:

1. A > D > C > B
2. A > D > B > C
3. D > C > B > A
4. C > B > D > A

Consider the following elements. [figure] Which of the following is/are true about A', B', C' and D' ? Choose the correct answer from the options given below :

1. A only
2. B, C and D only
3. A and B only
4. A, B and D only

If IUPAC name of an element is "Unununnium" then the element belongs to nth group of Periodic table. The value of n is .

Given below are two statements: In the light of the above statements, choose the most appropriate from the options given below:

1. Statement I is False but Statement II is true
2. Both Statement I and Statement II are False
3. Statement I is True But Statement II is False
4. Both Statement I and Statement II are True

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R : In the light of the above statements, choose the most appropriate from the options given below :

1. A is false but R is true
2. Both A and R are true but R is NOT the correct explanation of A
3. Both A and R are true and R is the correct explanation of A
4. A is true but R is false