Discuss the general characteristics and gradation in properties of alkaline earth metals.

Explanation

### Step-by-Step Solution

**Step 1: Introduction to Alkaline Earth Metals**
Alkaline earth metals are found in Group 2 of the periodic table and include beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). They are known for their characteristic properties and trends in behavior.

**Step 2: Physical Properties**
1. **Flame Colors**: Calcium, strontium, and barium exhibit characteristic colors when subjected to a flame test, while beryllium and magnesium do not show any distinct flame colors. This is due to the tightly bound electrons in beryllium and magnesium, which do not get excited easily.

...