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Chemistry 14.2. The Gas Laws. This hot air balloon was designed to carry a passenger around the world. You will study some laws that will allow you to predict gas behavior under specific conditions, such as in a hot air balloon. Boyle’s Law: Pressure and Volume.
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The Gas Laws • This hot air balloon was designed to carry a passenger around the world. You will study some laws that will allow you to predict gas behavior under specific conditions, such as in a hot air balloon.
Boyle’s Law: Pressure and Volume • Boyle’s Law: Pressure and Volume • How are the pressure, volume, and temperature of a gas related?
Boyle’s Law: Pressure and Volume • If the temperature is constant, • as the pressure of a gas increases, the volume decreases.
Boyle’s Law: Pressure and Volume • Boyle’s law states that for a given mass of gas at constant temperature, the volume of the gas varies inversely with pressure.
Boyle’s Law: Pressure and Volume • Simulation 15 • Examine the relationship between gas, volume and pressure.
Sample Problem Solution • 205 kPa X 4.00L = P2 X 12.0 L • P2 = 205 kPA X 4.00L = 68.3 kPa • 12.0L
Charles’s Law: Temperature and Volume • Charles’s Law: Temperature and Volume • As the temperature of an enclosed gas increases, the volume increases, if the pressure is constant.
Charles’s Law: Temperature and Volume • As the temperature of the water increases, the volume of the balloon increases.
Charles’s Law: Temperature and Volume • Charles’s law states that the volume of a fixed mass of gas is directly proportional to its Kelvin temperature if the pressure is kept constant.
Charles’s Law: Temperature and Volume • Simulation 16 • Examine the relationship between gas volume and temperature.
Gay-Lussac’s Law: Pressure and Temperature • Gay-Lussac’s Law: Pressure and Temperature • As the temperature of an enclosed • gas increases, the pressure increases, if the volume is constant.
Gay-Lussac’s Law: Pressure and Temperature • When a gas is heated at constant volume, the pressure increases.
Gay-Lussac’s Law: Pressure and Temperature • Gay-Lussac’s law states that the pressure of a gas is directly proportional to the Kelvin temperature if the volume remains constant.
Gay-Lussac’s Law: Pressure and Temperature • A pressure cooker demonstrates Gay-Lussac’s Law.
Gay-Lussac’s Law: Pressure and Temperature • Simulation 17 • Examine the relationship between gas pressure and temperature.
The Combined Gas Law • The Combined Gas Law • When is the combined gas law used to solve problems?
The Combined Gas Law • The combined gas law describes the relationship among the pressure, temperature, and volume of an enclosed gas.
The Combined Gas Law • The combined gas law allows you to do calculations for situations in which only the amount of gas is constant.
for Sample Problem 14.4 • Problem Solving 14.14 • Solve Problem 14 with the help of an interactive guided tutorial.
The Combined Gas Law • Weather balloons carry data-gathering instruments high into Earth’s atmosphere. At an altitude of about 27,000 meters, the balloon bursts.
14.2 Section Quiz. • 14.2.
14.2 Section Quiz. • 1. If the volume of a gas in a container were reduced to one fifth the original volume at constant temperature, the pressure of the gas in the new volume would be • one and one fifth times the original pressure. • one fifth of the original pressure. • four fifths of the original pressure. • five times the original pressure.
14.2 Section Quiz. • 2. A balloon appears slightly smaller when it is moved from the mountains to the seashore at constant temperature. The best gas law to explain this observation would be • Gay-Lussacs's Law. • Graham's Law. • Boyle's Law. • Charles's Law.