Why does hydration energy decreases with increase in ionic size?

Smaller the ion, the higher the hydration enthalpy will be because smaller atoms can accommodate a large number of water molecules around it and get hydrated. Hydration enthalpy decreases down the group the size of the atom increases due to the addition of extra valence shells.

Why are the hydration enthalpies of alkaline earth metal ions much larger than those for the alkali metal ions?

The hydration enthalpies of alkaline earth metals is larger than that of alkali metals due to their small size. Hence, due to greater nuclear charge on divalent cations, cations of alkaline earth metals are smaller in size than the cations of alkali metals.

Why heat of hydration of alkali metals decreases down the group?

Since size of atoms increases down the group in alkali metals and charge remains the same Hydration enthalpy decreases down the group which means Lithium have highest hydration enthalpy and Caesium have lowest hydration enthalpy among alkali metals.

Why hydration enthalpy is inversely proportional to size?

For group 1 elements, charge is constant (single positive charge). Hence, hydration enthalpy is inversely proportional to size. Size increases as we go down the group due to addition of more shells. Hence we can say that hydration enthalpy is maximum for lithium cation amongst the group 1 elements.

Why does hydration energy decrease down a group?

Smaller the ion, higher will be the hydration enthalpy because smaller atoms can accommodate a large number of water molecules around it, and gets highly hydrated. Hydration enthalpy decreases down the group because down the group size of the atom increases because of addition of extra valence shells.

How does the hydration energy of alkali metal cations vary on moving down the group?

Hydration enthalpy of alkali metals: The extent of hydration depends upon the size of the ions. Smaller the size of the ion, greater is the hydration enthalpy. On moving down the group, the metal ions increase in size and the lattice enthalpy decrease.

How does the hydration enthalpy of alkaline earth metals vary compare it with alkali metals?

The hydration enthalpies of alkaline earth metal ions decrease with increase in ionic size down the group. Thus compounds of alkaline earth metals are more extensively hydrated than those of alkali metals e.g. MgCl2 and CaCl2 exist as MgCl2.

What is hydration enthalpy of alkaline earth metals?

CBSE NCERT Notes Class 11 Chemistry The S Block Elements. The energy released as a result of the formation of new bonds between ions and water molecules is called hydration enthalpy. Hydration enthalpiesof alkaline earth metal ions decrease with the increasing ionic size down the group.

Why do hydration enthalpy decreases down the group?

The size of the hydration enthalpy is governed by the amount of attraction between the ions and the water molecules. The attractions are stronger the smaller the ion. For example, hydration enthalpies fall as you go down a group in the Periodic Table. The attractions are stronger the more highly charged the ion.

Why is the hydration of ions always a negative quantity?

Hydration enthalpies are always negative . In simple words it is the energy required to add one molecule of water to it. The size of the hydration enthalpy is governed by the amount of attraction between the ions and the water molecules. The attractions are stronger the smaller the ion. …

Is hydration energy inversely proportional to lattice energy?

Lattice energy increases as the charge on the ion increases and the size decreases. Hydration energy increases as the size of the ion decreases and charges on it increases.

Why does hydration energy increase during menstruation?

Hydration Energy significantly by moving from left to right in a period as the charge to size ratio increases, as found in the metal ions of the third period.