Considering the atomic number and position in the Modern periodic table, arrange the following elements in the increasing order of metallic character: `P, Mg, Ca, K, Si`.

Answer

To arrange the elements P (Phosphorus), Mg (Magnesium), Ca (Calcium), K (Potassium), and Si (Silicon) in increasing order of metallic character, we can follow these steps:

### Step 1: Understand Metallic Character
Metallic character refers to the tendency of an element to lose electrons and form positive ions (cations). Elements with higher metallic character tend to lose electrons more easily.

### Step 2: Identify the Position of Elements in the Periodic Table
- **Phosphorus (P)**: Group 15, Period 3
- **Silicon (Si)**: Group 14, Period 3
- **Magnesium (Mg)**: Group 2, Period 3
- **Calcium (Ca)**: Group 2, Period 4
- **Potassium (K)**: Group 1, Period 4

### Step 3: Determine the Trend of Metallic Character
- **Across a Period**: Metallic character decreases from left to right. Therefore, elements on the left (like Mg) are more metallic than those on the right (like P and Si).
- **Down a Group**: Metallic character increases as you move down a group. Therefore, K (in Group 1) is more metallic than Ca (in Group 2).

### Step 4: Compare the Elements
1. **Potassium (K)**: Most metallic due to being in Group 1 and Period 4.
2. **Calcium (Ca)**: Next in metallic character, being in Group 2 and Period 4.
3. **Magnesium (Mg)**: Less metallic than Ca, being in Group 2 but Period 3.
4. **Silicon (Si)**: Less metallic than Mg, being in Group 14 and Period 3.
5. **Phosphorus (P)**: Least metallic, being in Group 15 and Period 3.

### Step 5: Arrange in Increasing Order
Based on the above analysis, the increasing order of metallic character is:
**P < Si < Mg < Ca < K**

### Final Answer:
**P < Si < Mg < Ca < K**