Ideal Gas Law Calculator: Solve PV = nRT for Pressure, Volume, Moles or Temperature
ScienceFreeNo sign-up
Choose what to solve for and enter the other three values.
Solving PV = nRT for pressure gives 1.0006 atm. In SI units: P = 101,388.19 Pa, V = 0.022400 m³, n = 1.0000 mol, T = 273.1500 K.
Show the steps
- Convert to SI units: pressure in pascals, volume in cubic meters, temperature in kelvin. R = 8.314462618 J/(mol·K).
- P = nRT ÷ V
- Check: P × V = 2,271.10 J and n × R × T = 2,271.10 J.
Ideal gas law
P V = n R T
R = 8.314462618 J/(mol·K) = 0.082057 L·atm/(mol·K)
Kelvin = °C + 273.15
- The ideal gas law is accurate for gases at moderate pressure and fairly high temperature. At high pressure or low temperature real gases deviate.
Estimates for planning and learning, not financial, tax, legal or medical advice. Check figures with your lender, tax preparer or doctor before you act.
About this calculator
The ideal gas law, PV = nRT, links the pressure, volume, amount and temperature of a gas. Enter any three and this calculator finds the fourth, with automatic unit conversion.
Pressure can be in atm, kPa, Pa, bar, mmHg or psi. Volume can be in liters, mL, m³, ft³ or gallons. Temperature can be in °C, K or °F. The steps show the conversion to SI units and a check of both sides.
How to use it
- Choose which quantity to solve for.
- Enter the other three values and their units.
- Read the result, the conversions and the check.
Ideal gas law
- PV = nRT
- R = 8.314 J/(mol·K) = 0.08206 L·atm/(mol·K)
- Temperature must be in kelvin: K = °C + 273.15
Example
1 mole of gas at 0 °C (273.15 K) and 1 atm has volume V = nRT ÷ P = 0.08206 × 273.15 ÷ 1 = 22.41 liters. This is the molar volume at standard temperature and pressure.
Limits
Real gases behave like ideal gases at low pressure and high temperature. At high pressure or near condensation, the law becomes less accurate.
Sources
Quick check: test yourself
At constant temperature, if the volume of a gas halves, its pressure
Correct answer: doubles. P V = nRT: with n and T fixed, P is inversely proportional to V.
What must you do to a Celsius temperature before using PV = nRT?
Correct answer: Add 273.15 to get kelvin. The law needs absolute temperature in kelvin.
What is the volume of 1 mol of ideal gas at 0 °C and 1 atm?
Correct answer: 22.4 L. V = nRT ÷ P = 0.082057 × 273.15 ≈ 22.4 L.
Pick an answer for each question.
Common questions
What is the ideal gas law?
PV = nRT, where P is pressure, V volume, n moles, R the gas constant and T the absolute temperature.
Why must temperature be in kelvin?
The law relies on absolute temperature, where zero means no thermal motion.
What value of R is used?
8.314462618 J/(mol·K), which equals 0.082057 L·atm/(mol·K).
What is molar volume?
About 22.4 L per mole at 0 °C and 1 atm.
Can I use it for any gas?
It is a good approximation for most gases at ordinary conditions.
More science calculators
Related to This Article
More math articles
- Organizing government
- Free Mississippi MAAP Grade 3 Math Practice: 49 Printable PDFs for Classrooms, Tutors, and Parents
- Top 10 Tips to Create an ATI TEAS 7 Math Study Plan
- Using Number Lines to Represent Decimals
- The Ultimate PEAKS Algebra 1 Course (+FREE Worksheets)
- Middle-Range Theory and Evidence
- Free Grade 2 English Worksheets for North Dakota Students
- The Ultimate HiSET Math Formula Cheat Sheet
- 8th Grade DCAS Math Worksheets: FREE & Printable
- Propaganda, Wartime Civil Liberties, and Schenck
What people say about "Ideal Gas Law Calculator: Solve PV = nRT for Pressure, Volume, Moles or Temperature - Effortless Math"?
No one replied yet.