One Faraday of electricity will liberate 1g atom of the metal from the solution of

Options

A. NaCl
B. `BaCl_2`
C. `CuSO_4`
D. `AlCl_2`

Explanation

To solve the question of which metal will liberate 1 gram atom when 1 Faraday of electricity is passed through its solution, we can follow these steps:

### Step 1: Understand the concept of Faraday's law of electrolysis
Faraday's law states that the amount of substance liberated during electrolysis is directly proportional to the quantity of electricity passed through the solution. One Faraday (96485 coulombs) will liberate 1 equivalent of a substance.

### Step 2: Determine the equivalent weight of the metal
The equivalent weight of a metal can be calculated using the formula:
\[ \text{Equivalent weight} = \frac{\text{Atomic weight}}{\text{Valency}} \]
To liberate 1 gram atom of the metal, we need to find a metal whose equivalent weight corresponds to 1 gram.

### Step 3: Identify the valency of the metals
- For Sodium (Na) in NaCl: Valency = 1
- For Barium (Ba) in BaCl2: Valency = 2
- For Copper (Cu) in CuSO4: Valency = 2
- For Aluminum (Al) in AlCl3: Valency = 3

### Step 4: Calculate the equivalent weights
1. **Sodium (Na)**:
- Atomic weight = 23 g/mol
- Valency = 1
- Equivalent weight = 23/1 = 23 g (not 1 g atom)

2. **Barium (Ba)**:
- Atomic weight = 137 g/mol
- Valency = 2
- Equivalent weight = 137/2 = 68.5 g (not 1 g atom)

3. **Copper (Cu)**:
- Atomic weight = 63.5 g/mol
- Valency = 2
- Equivalent weight = 63.5/2 = 31.75 g (not 1 g atom)

4. **Aluminum (Al)**:
- Atomic weight = 27 g/mol
- Valency = 3
- Equivalent weight = 27/3 = 9 g (not 1 g atom)

### Step 5: Identify the metal that liberates 1 gram atom
To liberate 1 gram atom (which is equivalent to 1 equivalent weight), we need a metal with a valency of 1. The only metal from our examples that has a valency of 1 is Sodium (Na).

### Conclusion
Thus, when 1 Faraday of electricity is passed through a solution of Sodium chloride (NaCl), it will liberate 1 gram atom of Sodium.

### Final Answer
The metal that will liberate 1 gram atom when 1 Faraday of electricity is passed through its solution is Sodium (Na) from NaCl.

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