Which of the following statements accurately describes the electron affinity trend among halogens?

1. Br > F

2. F > Cl

3. Br > Cl

4. F > I

Which one of the elements has highest ionisation energy?

1. [Ne] 3s² 3p¹

2. [Ne] 3s² 3p²

3. [Ne] 3s² 3p³

4. [Ar] 3d¹⁰ 4s² 4p²

The electronegativity of the following elements increases in the order:

1. C, N, Si, P

2. N, Si, C, P

3. Si, P, C, N

4. P, Si, N, C

Which of the following has the highest electron affinity?

1. F^–

2. O^–

3. O

4. Na

The correct order of the decreasing ionic radii among the following isoelectronic species is:

1. Ca²⁺ > K⁺ >S^2–> Cl^–

2. Cl^– > S^2– > Ca^2– > K⁺

3. S^2– > Cl^– > K⁺ > Ca²⁺

4. K⁺ > Ca²⁺ > Cl^– > S^2–

The correct order of second ionisation energies of B , C , N & O is: 

1. O > N > C > B

2. O > C >N >B

3. O > B > C > N

4. O > N > B > C

The correct order of 3rd ionisation potential of Na, Mg, Al and Si is

1. Si > Al > Mg > Na

2. Mg > Si > Al > Na

3. Mg > Na > Si > Al

4. Mg > Na > Al > Si

Which pair has largest size difference?

1. Na and Na⁺

2. Na and K

3. Cl and Cl^–

4. Mg and Mg⁺

The order of electron gain enthalpy in the case of halogens is:

1. F > Cl > Br > I

2. I > Br > Cl > F

3. Cl > F > Br > I

4. I > Br > F > Cl