The amount of substance deposited by the passage of 1 A of current for 1s is equal to :

Options

A. Equivalent mass
B. Molecular mass
C. Electrochemical equivalent
D. Specific equivalent

Explanation

To find the amount of substance deposited by the passage of 1 A of current for 1 second, we can use Faraday's first law of electrolysis. Here’s a step-by-step solution:

### Step 1: Understand Faraday's First Law
Faraday's first law states that the amount of substance deposited or liberated at an electrode during electrolysis is directly proportional to the quantity of electricity passed through the electrolyte. The formula is given by:
\[ w = Z \cdot I \cdot t \]
where:
- \( w \) = weight of the substance deposited (in grams)
- \( Z \) = electrochemical equivalent (in grams per coulomb)
- \( I \) = current (in amperes)
- \( t \) = time (in seconds)

### Step 2: Substitute the Values
In this case, we have:
- \( I = 1 \, \text{A} \)
- \( t = 1 \, \text{s} \)

Substituting these values into the formula gives:
\[ w = Z \cdot 1 \cdot 1 = Z \]

### Step 3: Determine the Electrochemical Equivalent (Z)
The electrochemical equivalent \( Z \) can be expressed as:
\[ Z = \frac{E}{F} \]
where:
- \( E \) = equivalent weight of the substance (molecular weight / n-factor)
- \( F \) = Faraday's constant, which is approximately \( 96500 \, \text{C/mol} \)

### Step 4: Conclusion
Since we are asked for the amount of substance deposited by the passage of 1 A of current for 1 s, we conclude that:
\[ w = Z \]
Thus, the amount of substance deposited is equal to the electrochemical equivalent \( Z \) of the substance.

### Final Answer
The amount of substance deposited by the passage of 1 A of current for 1 s is equal to the electrochemical equivalent \( Z \).

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