Free Standard Temperature and Pressure MCQs with Answers
2 Standard Temperature and Pressure MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
2 questions
1. Standard temperature and pressure (STP) is defined as
- A. 25 degrees C and 1 atm
- B. 0 degrees C and 1 atm
- C. 0 K and 1 atm
- D. 25 degrees C and 760 mm of mercury above atmospheric
Explanation: STP is 273.15 K, which is 0 degrees Celsius, at a pressure of 1 atmosphere or 760 mm of mercury. One mole of any ideal gas occupies 22.4 dm3 under these conditions, which is the molar volume used throughout stoichiometry. The value of 25 degrees Celsius belongs to standard state conditions used in thermochemistry, a different convention.
Correct answer: 0 degrees C and 1 atm2. Standard temperature and pressure are defined as
- A. 25 degrees Celsius and 1 atm
- B. 0 degrees Celsius and 1 atm
- C. 0 K and 1 atm
- D. 100 degrees Celsius and 1 atm
Explanation: STP is 273.15 K, that is 0 degrees Celsius, at one atmosphere, and it is under these conditions that a mole of gas occupies 22.4 dm3. Room temperature and pressure, at 25 degrees, is a different reference where the molar volume is about 24 dm3. Quoting the wrong reference changes every subsequent calculation.
Correct answer: 0 degrees Celsius and 1 atm