The `pH` of milk, black coffee, tomato juice, lemon juice and egg white are `6.8, 5.0, 4.2, 2.2` and `7.8` respectively. Calculate corresponding hydrogen ion concentration in each.

Explanation

To calculate the hydrogen ion concentration corresponding to the given pH values of milk, black coffee, tomato juice, lemon juice, and egg white, we can use the formula:

\[ \text{[H}^+\text{]} = 10^{-\text{pH}} \]

Now, let's calculate the hydrogen ion concentration for each substance step by step.

### Step 1: Calculate [H⁺] for Milk (pH = 6.8)

1. **Given pH**: 6.8
2. **Calculate [H⁺]**:
\[ \text{[H}^+\text{]} = 10^{-6.8} \]
\[ \text{[H}^+\text{]} \approx 1.58 \times 10^{-7} \text{ M} \]

### Step 2: Calculate [H⁺] for Black Coffee (pH = 5.0)

1. **Given pH**: 5.0
2. **Calculate [H⁺]**:
\[ \text{[H}^+\text{]} = 10^{-5.0} \]
\[ \text{[H}^+\text{]} = 1.0 \times 10^{-5} \text{ M} \]

### Step 3: Calculate [H⁺] for Tomato Juice (pH = 4.2)

1. **Given pH**: 4.2
2. **Calculate [H⁺]**:
\[ \text{[H}^+\text{]} = 10^{-4.2} \]
\[ \text{[H}^+\text{]} \approx 6.31 \times 10^{-5} \text{ M} \]

### Step 4: Calculate [H⁺] for Lemon Juice (pH = 2.2)

1. **Given pH**: 2.2
2. **Calculate [H⁺]**:
\[ \text{[H}^+\text{]} = 10^{-2.2} \]
\[ \text{[H}^+\text{]} \approx 6.31 \times 10^{-3} \text{ M} \]

### Step 5: Calculate [H⁺] for Egg White (pH = 7.8)

1. **Given pH**: 7.8
2. **Calculate [H⁺]**:
\[ \text{[H}^+\text{]} = 10^{-7.8} \]
\[ \text{[H}^+\text{]} \approx 1.58 \times 10^{-8} \text{ M} \]

### Summary of Results:
- **Milk**: [H⁺] ≈ \(1.58 \times 10^{-7} \text{ M}\)
- **Black Coffee**: [H⁺] = \(1.0 \times 10^{-5} \text{ M}\)
- **Tomato Juice**: [H⁺] ≈ \(6.31 \times 10^{-5} \text{ M}\)
- **Lemon Juice**: [H⁺] ≈ \(6.31 \times 10^{-3} \text{ M}\)
- **Egg White**: [H⁺] ≈ \(1.58 \times 10^{-8} \text{ M}\)