Question

Describe the periodic properties of group 17 element of p block

Answer 1

Answer:

Group 17 Elements

The group 17 elements include fluorine(F), chlorine(Cl), bromine(Br), iodine(I) and astatine(At) from the top to the bottom. They are called “halogens” because they give salts when they react with metals. So, now you know what halogens are! Let’s now look at the electronic configuration of these elements.

Electronic Configuration of Group 17 Elements

The valence shell electronic configuration of these electrons is ns2np5. Thus, there are 7 electrons in the outermost shell of these elements.  The element misses out on the octet configuration by one electron. Thus, these elements look out to either lose one electron and form a covalent bond or gain one electron and form an ionic bond. Therefore, these are very reactive non-metals.

Atomic Properties

Let us now look at the various atomic properties of the group 17 elements. We will speak about the ionic and atomic radii, ionization enthalpy and more.

1) Ionic and Atomic Radii

The nuclear and atomic radii of these elements keep on increasing as we move down the group. This happens because of the addition of an extra energy level. They have the minimal atomic radii compared to the other elements in the related periods. This can be attributed to the fact that their atomic charge is quite powerful.

2) Ionisation Enthalpy

These elements have higher ionization enthalpy. This value keeps on diminishing as we move down the group. This happens because of the increase in the size of the nucleus. However, it is interesting to note that fluorine has the highest ionization enthalpy than any other halogen, thanks to its minute size!

3) Electron Gain Enthalpy

The electron gain enthalpy of these elements becomes less negative upon moving down the group. Fluorine has lesser enthalpy than chlorine. We can attribute it to the small size and the smaller 2p sub-shell of the atom of fluorine.

4) Electro-Negativity

The halogens exhibit high electro-negativity values. However, it diminishes slowly on moving down the group from fluorine to iodine. this can be attributed to the increase in nuclear radii upon moving down the group.

Explanation: