Pressure

Definition

Pressure is the force exerted per unit area on the surface of an object. It is commonly measured in units like Pascals (Pa) or atmospheres (atm).

5 Must Know Facts For Your Next Test

1. Pressure is calculated using the formula $P = \frac{F}{A}$, where $P$ is pressure, $F$ is force, and $A$ is area.
2. Standard atmospheric pressure at sea level is approximately 101.3 kPa or 1 atm.
3. The behavior of gases under different pressures can be described by Boyle's Law, which states that for a fixed amount of gas at constant temperature, pressure and volume are inversely proportional: $P_1V_1 = P_2V_2$.
4. Gas pressure can be measured using a manometer or a barometer.
5. In the ideal gas law, pressure ($P$) is one of the variables in the equation $PV = nRT$, where $n$ represents moles of gas and $R$ is the ideal gas constant.

Review Questions

• What formula is used to calculate pressure?
• How does Boyle's Law relate pressure and volume?
• What instruments are used to measure gas pressure?

Related terms

Boyle's Law:

States that for a fixed amount of gas at constant temperature, the volume of the gas varies inversely with its pressure.

Ideal Gas Law:

$PV = nRT$, an equation describing the state of an ideal gas in terms of its pressure, volume, temperature, and number of moles.

Manometer: A device used to measure the pressure of gases.