Exam 18: Thermal Properties of Matter

A container is filled with a mixture of helium (light molecules)and oxygen (heavy molecules)gases.A thermometer in the container reads 22°C.Which gas molecules have the greater average kinetic energy?

The figure shows a 50-kg frictionless cylindrical piston that floats on 0.68 mol of compressed air at 30°C.How far does the piston move if the temperature is increased to 300°C?

A sealed 89- tank is filled with 6000 moles of oxygen gas (O₂)at an initial temperature of 270 K.The gas is heated to a final temperature of 350 K.The ATOMIC mass of oxygen is 16.0 g/mol,and the ideal gas constant is = .The initial pressure of the gas is closest to

A sealed container holds 0.020 moles of nitrogen (N₂)gas,at a pressure of 1.5 atmospheres and a temperature of 290 K.The atomic mass of nitrogen is 14.0 g/mol.The Boltzmann constant is 1.38 × 10^-23 J/K and the ideal gas constant is = .The mass density of the gas is closest to

Assuming the radius of diatomic molecules is approximately for what pressure will the mean free path in room-temperature (20°C)nitrogen be 4.6 m? The Boltzmann constant is ,Avogadro's number is molecules/mole,and the ideal gas constant is =

What is the average translational kinetic energy per molecule of an ideal gas at a temperature of 300 K? The Boltzmann constant is .

A mole of oxygen (O₂)molecules and a mole of carbon dioxide (CO₂)molecules at the same temperature and pressure have

If the temperature of a fixed amount of an ideal gas is increased,it NECESSARILY follows that

The average molecular kinetic energy of a gas can be determined by knowing

The root-mean-square speed (thermal speed)of a certain sample of carbon dioxide molecules,with a molecular weight of 44 g/mol,is 396 m/s.What is the root-mean-square speed (thermal speed)of water vapor molecules,with a molecular weight of 18 g/mol,at the same temperature?

A weather balloon contains 12.0 m³ of hydrogen gas when the balloon is released from a location at which the temperature is 22.0°C and the pressure is 101 kPa.The balloon rises to a location where the temperature is -30.0°C and the pressure is 20.0 kPa.If the balloon is free to expand so that the pressure of the gas inside is equal to the ambient pressure,what is the new volume of the balloon? Assume that in both cases the hydrogen gas is in thermal equilibrium with the outside air.

The root-mean-square speed (thermal speed)of the molecules of a gas is 200 m/s at 23.0°C.At 227°C the root-mean-square speed (thermal speed)of the molecules will be closest to

A container is filled with a mixture of helium (light molecules)and oxygen (heavy molecules)gases.A thermometer in the reads 22°C.Which gas molecules have the greater average speed?

Eleven molecules have speeds 16,17,18,...,26 m/s.Calculate the root-mean-square of this group of molecules.

A sample of an ideal gas is slowly compressed to one-half its original volume with no change in pressure.If the original root-mean-square speed (thermal speed)of the gas molecules was V,the new speed is

What is the root-mean-square value of the following velocity components: 2.0 m/s,-3.0 m/s,and 4.0 m/s?

A hot air balloon has a volume of 2.00 × 10³ m³ when fully inflated,and the air inside the balloon is always at atmospheric pressure of 1.01 × 10⁵ Pa because of the large opening used to fill the balloon and heat the air inside it.What is the mass of hot air inside the balloon if its temperature is 120°C? The universal gas constant is 8.314 J/mol • K.(Assume a molecular weight of 28.8 g/mol for air.)

A 5.0-liter gas tank holds 1.4 moles of helium (He)and 0.70 moles of oxygen (O₂),at a temperature of 260 K.The atomic masses of helium and oxygen are 4.0 g/mol and 16.0 g/mol,respectively.Avogadro's number is 6.022 × 10²³ molecules/mol and the Boltzmann constant is .The total random translational kinetic energy of the gas in the tank is closest to