A water sample has ppm level concentration of the following metals : `Fe=0.2,Mn=5.0,Cu=3.0,Zn=5.0.` The metal that makes the water sample unsuitable for drinking is :

Options

A. 1.Fe
B. 2.Mn
C. 3.Cu
D. 4.Zn

Explanation

To determine which metal makes the water sample unsuitable for drinking, we need to compare the given concentrations of each metal with their maximum allowable limits in drinking water.

### Step 1: Identify the given concentrations of metals in the water sample.
- Iron (Fe) = 0.2 ppm
- Manganese (Mn) = 5.0 ppm
- Copper (Cu) = 3.0 ppm
- Zinc (Zn) = 5.0 ppm

### Step 2: Identify the maximum allowable concentrations for each metal in drinking water.
- Maximum allowable concentration for Iron (Fe) = 5 ppm
- Maximum allowable concentration for Manganese (Mn) = 0.05 ppm
- Maximum allowable concentration for Copper (Cu) = 3 ppm
- Maximum allowable concentration for Zinc (Zn) = 5 ppm

### Step 3: Compare the given concentrations with the maximum allowable concentrations.
- For Iron (Fe): 0.2 ppm < 5 ppm (acceptable)
- For Manganese (Mn): 5.0 ppm > 0.05 ppm (not acceptable)
- For Copper (Cu): 3.0 ppm = 3 ppm (acceptable)
- For Zinc (Zn): 5.0 ppm = 5 ppm (acceptable)

### Step 4: Determine which metal exceeds the maximum allowable concentration.
From the comparison, we see that:
- Manganese (Mn) has a concentration of 5.0 ppm, which exceeds the maximum allowable limit of 0.05 ppm.

### Conclusion:
The metal that makes the water sample unsuitable for drinking is **Manganese (Mn)**.

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