Charles-Law (1).pptx gas law that is part of kinetic molecular theory

gas law about charles law

1. CHARLES’ LAW

2. Charles’ Law The law states that “ the volume of a gas is directly proportional to its temperature if the pressure and the number of particles of the gas are constant”. One of the variable that affects the volume of a gas is the temperature of a gas and its surroundings.

3. Jacques Charles In 1787, Jacques Charles studied the relationship between the volume and temperature of a gas using a balloon. He concluded that when the pressure of the gas is kept constant, its volume is directly proportional to its temperature. This means that the volume of a gas increases as the temperature rises and the volume decreases as the temperature drops. This relationship is now known as Charles’ Law.

4. The temperatures are conventionally measured in Kelvin, the SI unit of temperature. The absolute temperature scale was devised by the English physicist Kelvin, so temperatures on this scale are called Kelvin (K) temperatures. The Kelvin scale must be used because zero on the Kelvin scale corresponds to a complete stoppage of molecular motion.

5. Mathematically, the direct relationship of Charles’ Law can be represented by the equation: V a T at constant pressure To remove the proportionality sign, a constant k is introduced. V = kT

6. If the same gas is brought to different temperatures, it will give two different volumes. The equation will become V 1 = V 2 T 1 T 2 where:
T1 = initial temperature of the gas T2 = final temperature of the gas
V1 = initial volume of the gas V2 = final volume of the gas

7. Any unit of the volume may be used, provided that the unit of V1 and V2 are the same. However, only Kelvin scale may be used for the temperature. The absolute temperature is temperature measured with the Kelvin scale.

8. Temperature Conversion Formulas

9. Real life Applications of Charles’ Law

10. PRACTICE A gas in a container has an initial volume of 2L and an initial temperature of 25°C. The final volume decreases to 0.25 L. What is the final temperature? A 36.4 L volume of methane gas is heated from 25° C to 88 °C at constant pressure. What is the final volume of the gas? The gas in a balloon measures 160 mL at 30 °C. What will be its volume if it is heated to 40°C?

11. QUIZ A 3.5 L flexible container holds a gas at 250 K. What will the new volume be if the temperature is increased to 400 K? A 275 mL balloon is filled with air at 25°C. If the temperature is increased to 50°C, what is the new volume of the balloon? The volume of a 500 mL container is decreased to 0.24 L. What is the new temperature in °C if the original temperature is 80°C?