Comprehension Passage
As one moves from left to right across a period in the periodic table, several key properties of elements exhibit consistent trends due to increasing nuclear charge and electrons being added to the same energy level. Firstly, atomic radius decreases due to greater attraction between the increasing positive nuclear charge and the electron cloud, pulling electrons closer. Ionization energy, the energy required to remove an electron, and electronegativity, the ability of an atom to attract electrons, both increase. This is because the tighter electron cloud makes it more difficult to remove an electron while also enhancing the atom's ability to attract electrons in bonds. These trends are fundamental in predicting and understanding the chemical behavior of elements.
For alkali metals, which one of the following trends is incorrect?
1
Ionisation energy : Li > Na > K > Rb
2
Atomic size : Li < Na < K < Rb
3
Density : Li < Na < K < Rb
4
Hydration energy : Li > Na > K > Rb