standard conditions
What standard conditions means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of standard conditions
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Reference: OCR
The agreed reference conditions of 100 kPa and a stated temperature, conventionally 298 K (25 °C), used so that enthalpy values can be compared between reactions.
298 K, a solution concentration of 1 mol dm⁻³ for each aqueous species, and a gas pressure of 100 kPa (1 bar) for any gaseous species.
Values are quoted at 298 K with every solution at 1.00 mol dm⁻³ and every gas at 100 kPa.
Using 1.00 mol dm⁻³ solutions at 298 K so the value may be quoted as standard.
Topics that use standard conditions
- Electrode potentials and cells (A-level only) (AQA A-Level)
- Enthalpy changes (OCR A-Level)
- Redox and electrode potentials (OCR A-Level)
Related terms
- feasibility prediction
- high-resistance voltmeter
- standard hydrogen electrode
- ∆H of combustion
- ∆H of formation
- Activation energy
- Applying familiar redox method to unfamiliar systems
- Approximate estimate
Using standard conditions in the exam
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