Short Answer TypeName the elements of group 2. Write down their electronic configurations ?
The metallic elements beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra) constitute group 2 of the periodic table. Radium is a radioactive element. These are known as alkaline earth metals.
Electronic configuration. The atoms of alkaline earth metals have two electrons in s-orbital outside a noble gas core. Therefore, their general electronic configuration is [Noble gas] ns2 where n = 2 to 7.
The electronic configuration of alkaline earth metals are given below:
| Element | At. No. | Electronic configuration |
| Beryllium (Be) | 4 | [He] s2 |
| Magnesium (Mg) | 12 | [Ne] 3s2 |
| Calcium (Ca) | 20 | [Ar] 4s2 |
| Strontium (Sr) | 38 | [Kr] 5s2 |
| Barium (Ba) | 56 | [Xe] 6s2 |
| Radium(Ra) | 88 | [Rn] 7s2 |
The alkaline earth metals are denser and harder than the corresponding alkali metals. Explain ?
What is the trend of atomic and ionic radii of alkaline earth metals within the group?
The atomic and ionic radii of alkaline earth metals are smaller than those of the corresponding alkali metals. Explain.
How will you explain that alkaline earth metals have much higher melting and boiling points than those of alkali metals?
The first ionisation enthalpies of alkaline earth metals are higher than those of corresponding alkali metals. Explain.
Second ionisation enthalpies of alkali metals are much higher than those of the alkaline earth metals. Explain.
How will you explain the electropositive or metallic character of alkaline earth metals?
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