Gases

Question 1

What is pressure?

Answer 1

The sum of the forces from all the molecular collisions

Question 2

What is the SI unit for pressure?

Answer 2

Pascal

Question 3

What is the conversion factor for giga?

Answer 3

10^9

Question 4

What is the conversion factor for mega?

Answer 4

10^6

Question 5

What is the conversion factor for kilo?

Answer 5

10^3

Question 6

What is the conversion factor for centi?

Answer 6

10^-2

Question 7

What is the conversion factor for milli?

Answer 7

10^-3

Question 8

What is the conversion factor for micro?

Answer 8

10^-6

Question 9

What is the conversion factor for nano?

Answer 9

10^-9

Question 10

What is the conversion factor for pico?

Answer 10

10^-12

Question 11

What is a barometer? How does it work?

Answer 11

A glass tube where the top is submerged in mercury and atmospheric pressure forces the mercury upwards

Question 12

What is the formula for atmospheric pressure in a barometer? What do variables stand for?

Answer 12

Patm=ghd

Patm is atmospheric pressure
h is height of liquid column
d is density
g is gravity

Question 13

How would you convert one bar to pascals?

Answer 13

Multiply by 100 000

Question 14

How can gas pressure be measured?

Answer 14

Manometer

Question 15

If height is equal in a manometer what does that mean about the pressure of the gas?

Answer 15

The pressure is the same btwn the atmosphere and gas

Question 16

If height of side exposed to atmosphere is higher in a manometer what does that mean about the pressure of the gas?

Answer 16

The gas pressure is greater

Question 17

If height of side exposed to atmosphere is lower in a manometer what does that mean about the pressure of the gas?

Answer 17

The pressure of the gas is less than the atmosphere

Question 18

What did Boyle’s law find? What is kept constant? What is formula?

Answer 18

Pressure and volume are inversely proportional

Temperature and moles

P1V1=P2V2

Question 19

What did Charles’s law find? What is kept constant? What is the formula? What unit for temperature is required?

Answer 19

Volume and temperature are directly proportional

Pressure and moles

V1/T1=V2/T2

Kelvin

Question 20

What does the combined gas law include? What is the formula? What unit must the temperature be in?

Answer 20

Boyle’s and Charles’s law

P1V1/T1=P2V2/T2

Kelvin

Question 21

What does Avogadro’s Law relate? What stays constant? What is the formula?

Answer 21

Volume is directly proportional to moles of gas

Temperature and pressure

V1/n1=V2/n2

Question 22

What does the ideal gas law include? What is the formula? What does temperature have to be in?

Answer 22

Boyle’s law, Charle’s law, and Avogadro’s law

PV=nRT

Kelvin

Question 23

What is one joule equivalent to?

Answer 23

Pam^3 or kpa L

Question 24

If we know the mass of a gas, what form of the ideal gas law can we use?

Answer 24

PV=(m/M)RT

Question 25

If we know the density what form of the ideal gas law can we use?

Answer 25

d=PM/RT

Question 26

If you have the total pressure and the percentage of each gas in the mixture how can you find their partial pressure?

Answer 26

Multiply the percent as a decimal by the total pressure

Question 27

What is the formula for total pressure?

Answer 27

Ptotal = Pa+Pb+Pc+…

Question 28

What is the mole fraction?

Answer 28

Moles of one thing/total moles Which is equal to partial pressure of the thing/total pressure

Question 29

What is the equation for collecting gases over water?

Answer 29

Ptotal=Pgas+Ph2o

Question 30

What is the volume of one mole of gas at stp?

Answer 30

22.7 L

Question 31

How do you find the limiting reagent?

Answer 31

Find moles and divide by coefficients in balanced chemical eqaution

Question 32

What does the kinetic molecular theory assume?

Answer 32

1. The size of gas particle is extremely small (negligible) 2. The avg kinetic energy of a particle is proportional to the temperature in Kelvin 3. No interaction during collision

Question 33

What is the formula for the avg kinetic energy of one particle? What do the variables represent?

Answer 33

KE=1/2mu^2 M is mass U is velocity

Question 34

What are the units for calculating root mean square velocity?

Answer 34

R- 8.314 j/molK T- Kelvin M- kg/mol

Question 35

What is the variation in speed with molar mass (graph)?

Answer 35

Gases with a lighter molar mass have a distribution that’s shifted toward higher velocity and a broader line

Question 36

What is the mean free path?

Answer 36

Average distance travelled between collisions

Question 37

What is effusion?

Answer 37

Gas escapes from container through small hole into a vacuum

Question 38

What is the difference in the equations for effusion rate and time?

Answer 38

In rate the rate and molar mass of same substance are in numerator and denominated and time the time and molar mass of same substance are in numerator or denominator togehter

Question 39

What causes gases to not act ideal?

Answer 39

High pressure and low temperatures