Created By : Rina Nayak

Reviewed By : Phani Ponnapalli

Last Updated : Apr 03, 2023

This Standard Temperature and Pressure Calculator is a simple tool that helps to determine the volume, number of moles of gas in standard conditions. It just takes the volume, pressure and temperature of the gas and inputs and produces the number of moles, volume of gas as output in a short span of time.

In Standard Conditions:
No. Of Moles

How to Find Volume, No of Moles at Standard Conditions?

Check out the detailed step by step process to compute the number of moles, the volume of the gas at standard conditions in the following sections.

  • Get the standard temperature and pressure, the volume of the gas.
  • Divide 273.15 by the temperature, pressure by 760
  • Multiply those values with the volume to get the volume at STP.
  • Divide the volume at STP by 22.4 to check the number of moles.

What is Standard Temperature and Pressure?

Standard temperature and pressure or STP or standard conditions are the same and it describes the environmental conditions for a chemical reaction.

The standard conditions of an ideal gas are listed here:

  • Standard temperature = 273.15 Kelvin = 0°C = 32°F. It is the freezing point of water
  • Standard pressure = 1 atm = 760 torr = 760 mm Hg = 101.35 kPa. It is the 1 atmosphere.
  • 1 mol of an ideal gas in the standard conditions have a volume of 22.4 litres.

STP Formulas

The formulas to calculate the volume and moles at STP conditions are given here:

VSTP = V * (273.15/T) * (P/760)

No. of Moles at STP = VSTP/22.4


V is the volume of the gas

T is the temperature of the gas

P is the pressure of the gas

Other formulas that can be used in this condition are:

Gay-Lussac's law: P₁T₂ = P₂T₁

Charles's law: V₁T₂ = V₂T₁

Boyle's law: P₁V₁ = P₂V₂


Question: If the gas temperature is 100 K, volume is 10 litres and pressure is 150 Pa. Find the volume and number of moles at STP?


Given that

Temperatute T = 100 Kelvin

Volume V = 10 litres = 0.01 m3

Pressure P = 150 Pa

VSTP = V * (273.15/T) * (P/760)

= 0.01 * (273.15/100) * (150/760)

= 40472.66 mm

Number of moles at STP = VSTP/22.4

= 40472.66/22.4

= 0.00180

Therefore, the number of moles, volume of the gas at Standard Temperature and Pressure is 0.00180, 40472.66 mm respectively.

At Chemistrycalc.Com, you will also discover different concepts calculators.

FAQ’s on STP Calculator

1. What is the STP formula?

The standard conditions formulas are based on ideal gas law i.e PV = nRT.

Volume at STP = V * (273.15/T) * (P/760)

Number of moles at STP = VSTP/22.4

2. How much is standard temperature and pressure?

The standard temperature is 273.15 K or 0°C or 32°F. It is also called the freezing point of water.

The standard pressure is 1 atm = 760 torr = 760 mmHg = 101.35 kPa.

3. What is the use of STP conditions?

STP conditions are useful to compare different sets of data. If we describe every reaction like the one that takes place in standard conditions, we can see the differences between them easily.

4. How to use standard temperature and pressure calculator?

You have to provide the volume, temperature and pressure of the gas and press the calculate button to know the volume, number of moles in the gas at standard conditions.

STP Calculator (Standard Temperature and Pressure)