Which member of the alkaline earth metals family has
(i)least reactivity (ii) lowest density (iii) highest boiling point (iv) maximum reduction potential ?

Explanation

To answer the question regarding the members of the alkaline earth metals family, we will analyze each part step by step.

### (i) Least Reactivity
1. **Identify the Group**: Alkaline earth metals belong to Group 2 of the periodic table, which includes Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), and Barium (Ba).
2. **Understand Reactivity Trend**: Reactivity in alkaline earth metals increases down the group due to increasing atomic size and decreasing ionization energy.
3. **Determine the Least Reactive Element**: Since Beryllium is the smallest in size and has the highest ionization energy, it holds onto its electrons more tightly than the others, making it the least reactive.

**Answer**: Beryllium (Be) has the least reactivity.
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