SB week 7

Select the statements that correctly describe how a barometer measures pressure. Select all that appl

-A column of mercury inverted in a dish of mercury measures pressure exerted on the open surface of the mercury -Pressure exerted by the atmosphere is equal to pressure exerted by the column of mercury.

Which of the following correctly describe gas law problems?

-An individual gas law can be used to solve problems where the change in one variable affects another while two other variables are held constant. -The ideal gas law can be used to solve problems where one variable is unknown and the rest are known.

Which of the following statements correctly describe the properties of gases? Select all that apply

-Gases have relatively low densities. -Temperature changes have a large effect on the volume of a gas. -Gases are much more compressible than liquids or solids.

Select the correct statements explaining how manometers measure the pressure of a gas in an experiment.

-In an closed-end manometer, the gas pressure is equal to the difference in column heights in the two arms of a U tube. -In an open-end manometer, the gas pressure pushes on the Hg surface on one arm of the U tube and atmospheric pressure gas pushes on the other. -The gas pressure is directly related to the height of a column of mercury it produces in a U tube.

Which of the following options correctly express the relationship between the volume and temperature of a gas at constant pressure? Select all that apply

-The volume of the gas is directly proportional to the absolute temperature. -As the temperature of the gas increases, the volume will increase.

A sample of nitrogen gas has a volume of 5.0 mL at a pressure of 1.50 atm. What is the pressure exerted by the gas if the volume increases to 30.0 mL, at constant temperature?

0.25atm

The abbreviation STP indicates a temperature of _____ and a pressure of _____.

0°C; 1 atm

A gas cylinder under constant pressure, such as one with a moveable piston, initially contains 0.25 moles of neon in 5.0 L. If 0.50 moles of helium are added to this gas cylinder, what will be the final volume?

15L

When the temperature of a 3.0-L sample of a gas at a pressure of 2.0 atm is increased from 10°C to 100°C, what will be the final pressure of the gas sample? Assume the volume remains constant.

2.6atm

What is the volume occupied by 1 mole of an ideal gas at STP?

22.4 L

At STP the volume of 1 mole of an ideal gas is always equal to_____ L (given to three significant figures.). This quantity is called the standard_____ volume.

22.4, molar

A gas is placed in a rigid container with a volume of 4.0 L. At 25°C the pressure exerted by the gas is 1.50 atm. What must the temperature be in order for the gas pressure to increase to 3.00 atm?

323 C

A sample of a gas has a volume of 52 L at a pressure of 1.2 atm. What volume will the gas occupy if the pressure is changed to 0.75 atm?

83L

Which of the following correctly describes an ideal gas?

A gas that obeys the gas laws under all conditions

What units can be used when performing a Boyle's law calculation?

Any units may be used as long as both the initial and final condition units match.

Which of the following statements correctly reflect the relationship between the volume and external pressure on a gas at constant temperature? Select all that apply

As pressure decreases, volume will increase. The external pressure increases as volume increases.

Select the statements that correctly describe how a barometer measures pressure.

Pressure exerted by the atmosphere is equal to pressure exerted by the column of mercury.

Consider a sample containing 1 mol of an ideal gas in a flexible, closed container. Which of the following changes will cause the volume to decrease? Select all that apply.

Temperature decreases while external pressure remains constant. Temperature decreases and external pressure increases.

How does a gas exert pressure?

The moving gas particles strike each other and the walls of the container, exerting a force.

A sample of gas is heated steadily in a closed rigid container. Which of the following correctly describes the result?

The pressure in the container will decrease. -The volume of the gas will increase -

A barometer, which is a device used to measure_____ pressure, consists of a vacuum tube containing a column of liquid such as mercury. The atmospheric pressure is proportional to the _____of the liquid column.

atmospheric, height

Charles's law states that for a gas at constant pressure, the volume occupied by a fixed amount of the gas is _____ proportional to the absolute temperature, i.e., the temperature measured in kelvins. This means that as the temperature increases the volume will _____.

directly; increase

A manometer operates on a principle similar to that of a barometer, except it is used to measure the pressure of _____.

enclosed gases

Pressure is defined as the______ exerted per unit of surface_______ .

force, area

The particles in a gas have a _____ distance between them than the particles of a liquid or a solid and their movement is random. Gas particles therefore move _____ freely than the particles of solids or liquids.

greater; more

A gas that exhibits simple linear relationships among the variables of temperature, volume, and pressure is called a(n) ______gas. No such gas actually exists, but most simple gases exhibit this behavior at ordinary______and pressures

ideal, temps

When converting a pressure from units of atmosphere (atm) to millimeters of mercury (mmHg), the numeric value will _____.

increase

At a fixed temperature and pressure, the volume occupied by a gas is _____ proportional to the number of moles of gas present. For ideal gases under these conditions, equal _____ of gas contain equal numbers of particles or moles.

inversely; volumes inversely; masses

Atmospheric pressure arises due to the force exerted by the air above the Earth. At higher altitudes, the mass of the air above the Earth is _____ than at sea level, and atmospheric pressure therefore _____ with altitude.

less; decreases

Gases tend to have _____ densities than either liquids or solids, and their _____ change greatly with changes in temperature or pressure.

lower; volumes

True or false: Temperatures must always be converted to the Kelvin temperature scale for gas law calculations.

t

Which of the following factors determine whether a given substance exists as a solid, liquid, or gas? Select all that apply.

temp, pressure

The ideal gas law is expressed as PV = nRT. In this equation, the symbol R indicates the ______gas constant, which may have different values depending on the units used to express______ and pressure.

universal, volume

A gas in a rigid container remains at constant____ even if the pressure and/or temperature are changed. The pressure exerted by the gas will ______as its temperature increases.

volume, increase

At fixed temperature and pressure, equimolar amounts of two ideal gases occupy equal

volumes

Absolute zero is the temperature at which an ideal gas would have _____ volume. This temperature corresponds to _____ °C Celsius and _____ K.

zero; -273.15; 0