What is not true about S.H.E.?

Options

A. Temperature is 273 K
B. Temperature is 271 K
C. `[H^(+)]=1M`
D. Pressure of `H_2=` 1 atm

Answer

To determine what is not true about the Standard Hydrogen Electrode (SHE), we can analyze the characteristics and conditions of SHE. Here is a step-by-step solution:

### Step 1: Understand the Standard Hydrogen Electrode (SHE)
The Standard Hydrogen Electrode is a reference electrode used in electrochemistry. It is defined under specific conditions.

### Step 2: Identify the standard conditions for SHE
The standard conditions for SHE are:
- Temperature: 298 K (25 °C)
- Pressure of hydrogen gas (H₂): 1 atm (or 101.3 kPa)
- Concentration of H⁺ ions: 1 M (which corresponds to a pH of 0)

### Step 3: Analyze the options given in the question
Assuming the options A, B, C, and D are statements about SHE, we will evaluate each option to see if it aligns with the standard conditions mentioned above.

### Step 4: Determine which statements are not true
- If any option contradicts the standard conditions (like incorrect temperature, pressure, or concentration), it is considered not true.

### Step 5: Conclusion
After evaluating the options:
- If options A and B contradict the standard conditions, they are the correct answers for what is not true about SHE.
- Options C and D would be true statements.

### Final Answer
Therefore, the statements that are not true about the Standard Hydrogen Electrode are options A and B.

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