What Does Hydration Energy Decrease Mean?
For understanding the concept of decrease in hydration energy, firstly, you have to know about hydration energy. Hydration energy is the energy released when one mole of ions are dissolved in the water. This makes an infinite dilute solution. For example, when one mole of any element, M is dissolved you will get Mz+(g) + mH2O ®Mz+(aq) where Mz+(aq) Now, every element has different amount of energy released when they are dissolved in water. When the atomic number increases then the ionic size increases and the hydration energy decreases. Hydration energy of all the elements in the periodic table is listed and the hydration energy usually decreases in the downward trend. Decrease in hydration energy means that low energy is released when one mole of ions are dissolved in water.
