Module 2: Foundations

Question 1

Define relative atomic mass

Answer 1

The weighted mean mass of an element relative to 1/12th of the mass of an atom of carbon-12

Question 2

Define relative isotopic mass

Answer 2

The mass of an isotope relative to 1/12th of the mass of an atom of carbon-12

Question 3

Define an ion

Answer 3

An electrically charged particle formed by the loss or gain of one or more electrons from an atom or group of atoms

Question 4

What is the formula to find the relative atomic mass?

Answer 4

sum of isotopic mass / sum of abundances (%)

Question 5

Define an isotope

Answer 5

An isotope is an element that has the same number of protons but a different number neutrons, therefore a different mass

Question 6

How many particles are in one mole?

Answer 6

6.02 x 10^23

Question 7

What is Avogadro’s Constant to find moles?

Answer 7

Number of particles / particles in a mole

Question 8

Define empirical formula

Answer 8

The simplest whole number ratio of atoms in a compound

Question 9

Define molecular formula

Answer 9

The actual number and type of atoms of each element in a compound

Question 10

Define anhydrous

Answer 10

Dry, no water present

Question 11

Define hydrated

Answer 11

A molecule that contains water

Question 12

Define water of crystallisation

Answer 12

Water molecules forming an essential part of the crystal structure in a compound

Question 13

Define stiochiometry

Answer 13

Relationship between the amount of reactants and products in a chemical reaction

Question 14

What is the moles equation in relation to mass?

Answer 14

n = m/Mr

Question 15

What is the moles equation for solutions?

Answer 15

n = c x v

Question 16

How do you convert from cm3 to dm3?

Answer 16

Divide by 1000

Question 17

What is a standard solution?

Answer 17

A solution with a known concentration

Question 18

What is RTP?

Answer 18

Regular temperature and pressure, which is 20 oC and 101 kPa

Question 19

What is the equation for moles at RTP?

Answer 19

n = V/24

Question 20

What is the ideal gas equation?

Answer 20

pV = nRT

Question 21

In the ideal gas equation, what is ‘R’?

Answer 21

Ideal gas constant, which is 8.314 Jmol -1 K -1

Question 22

For the ideal gas equation, what units do the components need to be in?

Answer 22

P = pressure, Pascals
V = volume, m3
n = moles, mol
R = ideal gas constant, Jmol -1 K -1
T = temperature, K (Kelvin)

Question 23

How do you convert cm3 into m3?

Answer 23

Multiply by 10^-6

Question 24

How do you convert dm3 into m3?

Answer 24

Multiply by 10^-3

Question 25

How do you convert from celcius to Kelvin?

Answer 25

+273

Question 26

How do you convert from kPa to Pa?

Answer 26

Multiply by 10^3

Question 27

What is the equation for percentage yield?

Answer 27

Percentage yield = actual yield / theoretical yield x 100

Question 28

What is a limiting reagent?

Answer 28

A reactant that prevents the reaction from going on

Question 29

What is the equation for atom economy?

Answer 29

Atom economy = sum of desired products/sum of all products x 100

Question 30

How could you increase atom economy to improve sustainability?

Answer 30

Use other products for different purposes, find another reaction for desired product that is more sustainable

Question 31

Are common salts of sodium, potassium and ammonium soluble?

Answer 31

Yes

Question 32

Are nitrates soluble?

Answer 32

Yes

Question 33

Are common chlorides soluble?

Answer 33

Yes, except silver and lead

Question 34

Are common sulfates soluble?

Answer 34

Yes, except lead, barium and calcium

Question 35

Are common carbonates and hydroxides soluble?

Answer 35

No, except sodium, potassium and ammonium