Experimental Design & Practice 1 (Ideal Gases)

Question 1

What are the Gas laws

Answer 1

Relationships between different variables we use to describe gases

Pressure (kPa)
Volume (L)
Temp (Kelvin)
Amount (mols)

Question 2

What are the 5 gas laws we are to learn?

Answer 2

Boyle’s Law
Charles’s Law
Gay Lussac’s Law
Avogadro’s Law
Combined Gas Law

First 4 laws compares 2 variables at a time

Question 3

Boyle’s Law

Answer 3

When the pressure of a gas increases the vol decreases, given that the temp and amount of gas are held constant.

They’re inversely proportional

Question 4

Boyle’s Law (Comparing an initial set of conditions to a change set of conditions)

Answer 4

P1V1 = P2V2

Question 5

Charles’s Law

Answer 5

As temp of a gas increases the vol of gas also increases, given that pressure and amount of gas held constant

Temp and vol are directly proportional

Question 6

Charles’s Law (Comparing an initial set of conditions to a change set of conditions)

Answer 6

V1/T1 = V2/T2

Question 7

Gay Lussac’s Law

Answer 7

As temperature of a gas increases, the pressure of a gas also increases, given that the vol and amount of gas is constant

Pressure and Temperature are directly proportional

Question 8

Gay Lussac’s Law (Comparing an initial set of conditions to a change set of conditions)

Answer 8

P1/T1 = P2/T2

Question 9

Avogadro’s Law

Answer 9

As you increase the amount of a gas, the vol of the gas will increase.

They are directly proportional

Question 10

Avogadro’s Law (Comparing an initial set of conditions to a change set of conditions)

Answer 10

V1/n1 = V2/n2

Question 11

Combined Gas Law

Answer 11

Combines Boyle’s, Charles’s and Gay Lussac’s Law tight together

Links Pressure, Volumen and Temperature

PV=T

PV / T = Constant

Question 12

Combined Gas Law (Comparing an initial set of conditions to a change set of conditions)

Answer 12

P1V1 / T1 = P2V2 / T2

This allows not just one but two of the variables to change

Question 13

Make sure your temperature value is always in….
When working with ideal gases

Answer 13

Kelvin

0K = 273.15 Celcius

Question 14

Validity refers to what?

Answer 14

Validity refers to how accurately a method measures what it is intended to measure.

Question 15

PV = mRT
or
PV = nRuT

Answer 15

m: mass, R: gas constant (different value for different gases, e.g. for
air R = 287.1 J/kg K and for CO2 R = 188.9 J/kg K)
* n: number of moles, Ru
: universal gas constant = 8.3145 J/mol K
(same value for all gases)\

Knowing that molar mass M = m/n (kg/mol) → R = Ru
/M

Question 16

Different ways of measuring temperature (5):

Answer 16

Liquid Expansion Thermometer
Thermocouples, Used in ideal gas experiment
Resistance Sensor
Bimetallic Device
Infrared Sensor (thermal radiation (For surface temperature)