The most abundant alkaline earth metal is ________.

Answer

To determine the most abundant alkaline earth metal, we can follow these steps:

1. **Identify Alkaline Earth Metals**: The alkaline earth metals belong to Group 2 of the periodic table. The main elements in this group are beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).

2. **Research Abundance**: To find out which of these metals is the most abundant in the Earth's crust, we can refer to geological data or periodic table information that indicates the abundance of elements.

3. **Find the Most Abundant Metal**: Among the alkaline earth metals, calcium (Ca) is known to be the most abundant. It is the fifth most abundant element in the Earth's crust overall.

4. **Conclusion**: Based on the information gathered, we conclude that the most abundant alkaline earth metal is calcium.

**Final Answer**: The most abundant alkaline earth metal is calcium.

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