# Ch 11 chemistry

.50 mol

What is the number of moles of H2 produced when 23 g of sodium react with water according to the equation 2Na(s) + 2H2O(l) -->2NaOH(aq) +H2(g)?

3.0 atm

What is the pressure exerted by 1.2 mol of a gas with a temperature of 20°C and a volume of 9.5 L?

Effusion

What is the process by which molecules of a gas randomly encounter and pass through a small opening in a container?

22.4 L

What is the volume occupied by 1 mole of oxygen at STP?

22.4 L

What is the volume occupied by 1 mole of water vapor at STP?

Charles law

When the ideal gas law reduces to V= kT, got expression is equivalent to

Your ears are releasing pressure to equal the pressure of the atmosphere pushing on your body.

Why do your ears "pop" in an airplane?

Pressure and temperature are directly related, so the lower the pressure, the lower the temperature.

Why is the boiling point of a substance low pressure lower than the boiling point and standard pressure?

Dalton's law of partial pressures

the total pressure of a gas mixture is the sum of the partial pressure of the component of gasses

STP

22.41 L is the volume of 1 mol of any gas at ____________.

16.0 g/mol

A 1.00 L sample of a gas has a mass of .716 g at STP. What is the molar mass of the gas?

28.0 g/mol

A 1.00 L sample of a gas has a mass of 1.25 g at STP. What is the mass of 1 mole of this gas?

38 g/mol

A 1.00 L sample of a gas has a mass of 1.7 g at STP. What is the molar mass of this gas?

43.0 g/mol

A 1.00 L sample of a gas has a mass of 1.92 g at STP. What is the molar mass of the gas?

27.7 g

A 2.00 L sample of a gas has a mass of 2.47 g and STP, the molar mass of the gas is ___________.

108 g/mol

A gas sample with a mass of .250 g is collected at 150°C and 720 mmHg. The volume is 85 mL. What is the molar mass of the gas?

58 g/mol

A gas sample with a mass of .467 g is collected at 20°C and 732.5 mm Hg. The volume is 200 mL. What is the molar mass of the gas?

116 g/mol

A gas sample with a mass of .934 g is collected at 20°C and 733.5 mmHg. The volume is 200 mL. What is the molar mass of the gas

The Ideal Gas Law

A mathematical relationship among pressure, volume, temperature, and the number of moles of gas. PV=nRT

69.7

A pressure of 523 mm Hg is equal to ______________ kPa.

.39 mol

A sample of gas at 25°C has a volume of 11 L and exerts a pressure of 600 mm Hg. How many moles of gas are in the sample?

The square root of their molar mass

According to Graham's law, The rates of diffusion of two gases at the same temperature and pressure are inversely proportional to

Molar masses

According to Graham's law, two gases at the same temperature and pressure will have different rates of diffusion because they have different

P=nRTV

All of the following equations are statements of the ideal gas law except

Number of moles of gas

At STP, the standard molar volume of a gas of known volume can be used to calculate the

Temperature and pressure

At constant ________________________, gas volume is directly proportional to the number of moles of gas.

Number of moles of gas

At constant temperature and pressure, gas volume is directly proportional to the

Gay- Lussac's law of combing volumes of gases

At constant temperature and pressure, the volumes of gaseous reactants and products can be expressed as ratios of small whole numbers (the exact same as stoichemetry mole ratios)

4.07 L

Calculate the approximate volume of a .350 mol sample of a gas at 25°C and a pressure of 2.10 atm

Temperature

Charles law is the direct relationship between _______________ amd volume.

Molecules

Equal volumes of diatomic gases under the same conditions of temperature and pressure contains the same number of

Avogrado's Law

Equal volumes of gases at the same temperatures and pressure contain equal numbers of molecules

Standard temperature and pressure (STP)

For purposes of comparison, scientists have agreed on standard conditions which are known as STP. STP - 1 atm, 0°C or 273 K

Equal

The law of combining volumes applies only to ___________ volumes measured at constant temperature and pressure.

Effusion

The passage of gas particles through a small opening is called ______________.

Partial

The pressure of each gas in a mixture is called the __________ pressure.

Partial pressure

The pressure of each gas in a mixture of gases

Avogrado

The principle that under similar pressures and temperatures, equal volumes of gases contain the same number of molecules is attributed to ______________.

Graham's law of effusion

The rates of effusion of gases at the same temperature and pressure are inversely proportional to the square root of their molar masses. Square root of molar mass ratio= inverse ratio of rates of effusion

Gas stoichemetry

The reaction of two volumes of hydrogen gas with one volume of oxygen gas to produce two volumes of water vapor is an example of __________________.

Standard molar volume of gas

The volume occupied by one mole of gas at STP, is 22.4 L. Conversion factor at STP is 22.4 L. R= .0821

Decreases

The volume of a gas ____________ during compression.

The gases law

Simple mathematical relationships between the volume, pressure, temperature, and amount of gas

0,1

Standard temperature and pressure is equal to ___________ °Celsius and _________ atm.

Closer to the end that held the heavier gas

Suppose that two gases with unequal molar masses were injected into opposite ends of a long tube at the same time and allowed to diffuse toward the center. They should begin to fix

Pascals

The SI unit for pressure is the _____________.

Kinetic molecular

The ______________________ Theory says particles of matter are in constant motion.

Gay Lussac's law

The direct relationship between temperature and pressure is known as ___________________.

Diffusion

The gradual mixing of two or more gases due to their spontaneous, random motion

The number of moles and the pressure are constant

The ideal gas law is equivalent to Charles law when

The pressure and the temperature are constant

The ideal gas law is equivalent to avogadros law when

Inversely

Graham's Law of diffusion states that the rate of diffusion is ____________ proportional to the square root of the gas's density.

They mix with other gases in the room to fill the container.

How do substances move during diffusion?

Charles law

If n and p are constant, The ideal gas law reduces two

Double

If the volume of gas particles is cut in half, then the pressures will ______________ in a fixed amount of gas.

2

In the equation H2(g) + Cl2(g)--> 2HCl(g), One volume of hydrogen you how many volumes of hydrogen chloride?

Barometer

Is a device used to measure atomic pressure - Evangelista Torricelli discovered the pressure of the Adam supports a column of mercury about 7600 mm

Pressure

Is defined as the force per unit area on a surface. *units of force are newtons (N). Pressure= force over area

Effusion

Is the process whereby the molecules of a gas confined in a container randomly pass through a tiny opening in the container.

Molar mass

Knowing the mass and volume of a gas at STP allows one to calculate the ______________.

Boyles law

Pressure and volume changes at a constant temperature can be calculated using ___________________.

Area

Pressure is the force per-unit _____________.