Answer:
43 mole
Explanation:
Given data:
Number of atoms of Li = 2.6× 10²⁵ atoms
Number of moles = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
2.6× 10²⁵ atoms × 1 mole / 6.022 × 10²³ atoms
0.43 × 10² mole
43 mole
Answer:
Electrons arrangement change is almost constant down the group, hence nuclear charge is almost constant.
But the energy levels on which electrons are arranged increase down the group, hence shielding or screening effect increases.