Charles's Law describes the quantitative relationship between the temperature and volume of a gas, stating that the volume of a given mass of gas is directly proportional to the absolute temperature when pressure is constant. This law was formulated by French scientist J. Charles in 1787. The equation V/T = k is used to verify this relationship, where V represents volume, T is temperature, and k is a constant. The law is experimentally verified by observing that the ratio of volume to temperature remains constant for the same amount of gas at the same pressure.
Which temperature scale is used to verify V/T = k in Charles's Law?
The Kelvin scale of temperature is used to verify V/T = k in Charles's Law. This is because Charles's Law is obeyed when temperature is measured on the Kelvin scale.
Explain the idea of absolute zero derived from Charles's Law.
Absolute zero is derived from Charles's Law by observing that at -273.16 °C (0 Kelvin), the volume of a gas theoretically becomes zero. This concept helps establish -273.16 °C as the coldest temperature possible.
What is the Kelvin scale of temperature?
The Kelvin scale of temperature is an absolute temperature scale where 0 Kelvin represents absolute zero. It is used in scientific calculations, especially in gas laws like Charles's Law.
What is the significance of the factor 1/273 in Charles's Law?
The factor 1/273 in Charles's Law signifies that the volume of a gas changes by 1/273 of its original volume at 0 °C for every 1 °C rise or fall in temperature. This factor is crucial in understanding the relationship between volume and temperature in gases.
How is the general gas equation derived?
The general gas equation is derived by combining Boyle's Law, Charles's Law, and Avogadro's Law when none of the variables are held constant. The equation PV = nRT represents the general gas equation, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is the absolute temperature.
What is the new temperature when a gas is cooled from 25.0°C to occupy a volume of 100.0 mL?
a) 198.8K
b) -74.4°C
c) 273K
d) 100°C
Answer: a) 198.8K
What happens to the volume of a gas when its temperature is decreased at constant pressure?
a) Increases
b) Remains constant
c) Decreases
d) Doubles
Answer: d) Doubles
Can we determine the molecular mass of an unknown gas if we know the pressure, temperature, and volume along with the mass of that gas?
a) Yes
b) No
c) Maybe
d) Not sure
Answer: a) Yes
What is Avogadro’s law of gases?
a) The volume of a gas is inversely proportional to its pressure
b) Equal volumes of gases at the same temperature and pressure contain equal numbers of molecules
c) The volume of a gas is directly proportional to its temperature
d) The volume of a gas is directly proportional to its pressure
Answer: b) Equal volumes of gases at the same temperature and pressure contain equal
numbers
of molecules
Why do we feel comfortable expressing the densities of gases in the units of g dm-3 rather than g cm-3?
a) Due to historical reasons
b) To maintain consistency with liquid and solid densities
c) To confuse students
d) No specific reason
Answer: b) To maintain consistency with liquid and solid densities