Ch. 5 - Gases

Question 0

Millimeter of Mercury (mmHg)

Answer 0

• a common unit of pressure
• originates from how pressure is measured with a barometer
• often call a torr

Question 1

Pressure

Answer 1

• the force exerted per unit area by gas molecules as they strike the surfaced around them

= force ➗ area

Question 2

Barometer

Answer 2

• an evacuated glass tube, the tip of which is submerged in a pool of mercury
• liquid in an evacuated tube is forced upward by atmospheric gas pressure on the liquid’s surface

Question 3

Atmosphere (atm)

Answer 3

• a second unit of pressure
• the average pressure at sea level
• 1 atm = 760 mmHg

Question 4

Pascal (Pa)

Answer 4

• the SI unit of pressure
• defined as 1 newton (N) per square meter
• 1 atm = 101,325 Pa

Question 5

Inches of Mercury (in Hg)

Answer 5

• 1 atm = 29.92 in Hg

Question 6

Pounds Per Square Inch (psi)

Answer 6

• 1 atm = 14.7 psi

Question 7

Boyle’s Law

Answer 7

• as pressure increases, volume decreases

Question 8

Charle’s Law

Answer 8

• as temperature increases, volume increases

Question 9

Avogadro’s Law

Answer 9

• as amount of gas increases, volume increases

Question 10

The Ideal Gas Law

Answer 10

PV = nRT

Question 11

Molar Volume

Answer 11

• the volume occupied by one mole of a substance

Question 12

Standard Temperature and Pressure (STP)

Answer 12

• this often specifies the molar volume of gases under conditions

Question 13

Density

Answer 13

= molar mass ➗ molar volume

Question 14

Hypoxia

Answer 14

• oxygen starvation
• mild causes dizziness, headache, and shortness of breath
• severe may result on unconsciousness or even death

Question 15

Oxygen Toxicity

Answer 15

• the increased oxygen concentration in body tissues

- results in muscle twitching, tunnel vision, and convulsions

Question 16

Nitrogen Narcosis

Answer 16

• when the pressure of nitrogen increases beyond 4 atm
• divers describe it as feeling inebriated or drunk
• AKA Rapture of the Deep

Question 17

Kinetic Molecular Theory

Answer 17

• the size of a particle is negligibly small
• the average kinetic energy of a particle is proportional to the temperature in kelvins
• the collision of one particle with another (or with the walls of its container) is completely elastic

Question 18

Dalton’s Law

Answer 18

• the total pressure of a gas mixture is the sum of the partial pressures of its components

Question 19

Mean Free Path

Answer 19

• the average distance that a molecule travels between collisions

Question 20

Diffusion

Answer 20

• the process by which gas molecules spread out in response to a concentration gradient

Question 21

Effusion

Answer 21

• the process by which a gas escapes from a container into a vacuum through a small hole