Conditions of standard state used in thermochemistry is

Options

A. `0^(@)C` and 1 atm
B. `20^(@)C` and 1 atm
C. `25^(@)C` and 1 atm
D. 0K and 1 atm

Answer

To answer the question regarding the conditions of standard state used in thermochemistry, we can break it down into the following steps:

### Step 1: Define Standard State
The standard state refers to a set of specific conditions under which thermodynamic measurements are made. It provides a reference point for comparing thermodynamic properties.

### Step 2: Identify Standard Temperature
The standard temperature is defined as 25 degrees Celsius, which is equivalent to 298 Kelvin. This temperature is commonly used in thermochemical calculations.

### Step 3: Identify Standard Pressure
The standard pressure is defined as 1 atmosphere (atm). This pressure is used as a reference point for gases in thermodynamic equations.

### Step 4: Summarize the Conditions
Thus, the conditions of the standard state in thermochemistry are:
- Temperature: 25 degrees Celsius (298 Kelvin)
- Pressure: 1 atmosphere

### Step 5: Conclusion
In conclusion, the correct answer to the question is that the conditions of standard state used in thermochemistry are 25 degrees Celsius and 1 atmosphere.

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