# Standard conditions vs. Standard state

• Bipolarity
In summary, standard conditions refer to a specific set of temperature and pressure values, such as STP or SATP, while standard state refers to a set of conditions that allow for comparison and calculation of thermodynamic properties. Standard state is often used in more advanced chemistry, such as geochemistry, and includes an idealization of gas or solution behavior.
Bipolarity
What's the difference between standard conditions and standard state? I noticed in my thermodynamics chapter that in standard state, the reaction quotient is 1 because all activities are equal to 1 (if I remember correctly).

Standard conditions is about standard temperature and pressure right?

Well is there any relation between the two terms? Anything that has to do with thermodynamics?

Thanks!

BiP

Standard Temperature and Pressure (STP) is considered to be 0°C and 1 bar. Because of the fact that STP requires a refrigerator to exist, many people will mention Standard Ambient Temperature and Pressure (SATP), which is 25°C and 1 bar. This should be, hopefully, the conditions at your typical lab bench. :)

A standard state is different. It's a set of conditions which allows for fairly easy comparisons of thermodynamic properties (and calculations thereof). While the standard state quantities one sees in textbooks for secondary level and introductory university level chemistry are for STP and/or SATP, they're not the only ones by any means. For example, if one gets into geochemistry, you're going to need standard state values at pressures nowhere near those values for doing your work. There's also an idealization of either gas or solution behavior (e.g., ideal gas behavior or infinite dilution limit).

## 1. What are standard conditions and standard state?

Standard conditions refer to a set of defined parameters, such as temperature and pressure, used in scientific experiments and calculations. Standard state refers to the specific physical state of a substance under these standard conditions.

## 2. Are standard conditions and standard state the same thing?

No, they are not the same thing. Standard conditions refer to a set of parameters, while standard state refers to the physical state of a substance under those conditions.

## 3. What is the purpose of using standard conditions and standard state?

Using standard conditions and standard state allows for consistency and comparability in scientific experiments and calculations. It provides a standardized baseline for measuring and comparing results.

## 4. How do standard conditions and standard state affect the properties of a substance?

Standard conditions and standard state can affect the properties of a substance, such as its boiling point and melting point, by providing a set of consistent parameters that can influence the behavior of the substance.

## 5. Can standard conditions and standard state change?

Yes, standard conditions and standard state can change depending on the specific experiment or calculation being performed. In some cases, different standard conditions may be used for different experiments, but the standard state of a substance will remain the same under those specific conditions.

Replies
2
Views
1K
Replies
1
Views
1K
Replies
6
Views
3K
Replies
4
Views
3K
Replies
22
Views
8K
Replies
4
Views
2K
Replies
17
Views
2K
Replies
1
Views
1K
Replies
21
Views
898
Replies
2
Views
2K