OUTCOME 3 - moles + organic compounds

Question 1

mass spectrometer use

Answer 1

a scientific instrument used to:

• Determine the relative atomic mass (Aᵣ) of an element
• Identify elements or compounds
• Find the molecular mass (Mr) of a compound
• Analyse isotope patterns

Question 2

Define relative isotopic mass

Answer 2

The mass of an atom of the isotope relative to the mass of an atom of carbon-12 taken as 12 units exactly

Question 3

Define relative atomic mass

Answer 3

The weighted average of the relative isotopic masses of an element
on the scale where 12C is 12 units exactly.
- symbol = Ar

Question 4

Calculate relative atomic mass

Answer 4

Ar = (isotope1mass×%abundance) +(isotope2mass×%abundance)
DIVIDED BY 100

Question 5

Define molar mass (M)

Answer 5

The mass of 1 mole of a substance
(measured in g mol−1).
- symbol = M

Question 6

Calculate molar mass

Answer 6

1. find atomic mass of each element
2. multiply by how many atoms of each element IF given
3. add them all together

example: H2O (H - m of 1) (O -m of 16)
M = (2×1)+ (1×16)
=2+16
=18g/mol

Question 7

What element is used as a basis for relative atomic mass and why

Answer 7

Carbon 12
- stable and common
- one atom of carbon-12 is exactly 12 units of mass

Question 8

Define mole (n)

Answer 8

The amount of substance that contains
the same number of fundamental particles as there are atoms in 12 g of carbon-12;

• symbol = n
• unit = mol.

Question 9

Explain what Avogadro’s number (NA) is

Answer 9

the number of particles (atoms, molecules, or ions) in 1 mole of a substance

NA = 6.022 × 10²³

Question 10

formula 1 (n’s)

Answer 10

n = N/NA

Question 11

formula 2 (m’s)

Answer 11

n = m/M

Question 12

Calculate percentage composition of elements in compounds

Answer 12

(Totalmassoftheelementinthe
compound / molar mass of compound) x 100

Question 13

calculate empirical formula

Answer 13

1. Write the mass or percentage of each element.
2. Divide by the atomic mass (Aᵣ) to get moles.
3. Divide all mole values by the smallest one.
4. Write the formula using whole numbers.

Question 14

Calculate molecular formula

Answer 14

n = molecular mass / empirical formula mass

Question 15

Describe what hydrated ionic compounds are

Answer 15

Ionic compounds that have water molecules chemically bonded to them as part of their solid structure

Question 16

Calculate the percentage composition of water in hydrated compounds

Answer 16

1.) Write the formula of the hydrated compound (e.g. CuSO₄·5H₂O).
2.) Find the molar mass (Mr) of the whole compound, including water.
3.) Find the mass of just the water (number of H₂O × 18)
4.) (mass of water/total molar mass) x 100

Question 17

Intramolecular bonding in hydrocarbons

Answer 17

• bonds within a molecule
• Colavent bonds
• C and H share electrons

Question 18

Intermolecular bonding in hydrocarbons

Answer 18

• forces between molecules
• weak (dispersion forces)
• affect BP and MP

Question 19

Homologous series

Answer 19

group of organic compounds with:
- same functional group
- same general formula
- similar chemical properties

Question 20

Saturated

Answer 20

compound w/ only SINGLE bonds between carbons (alkanes)

Question 21

Unsaturated

Answer 21

A compound with at least one double bond between carbon atoms
(alkenes)

Question 22

Isomers

Answer 22

compounds w/ same molecular formula but different structures

Question 23

Alkanes

Answer 23

• single bonds
• saturated
• less reactive
• CnH2n+2
  example: methane

Question 24

Alkenes

Answer 24

• at least 1 double bond
• unsaturated
• more reactive
• CnH2n
  example: ethene

Question 25

Molecular formula

Answer 25

number of each atom in the molecule example: Ethanol = C₂H₆O

Question 26

Semi-structural formula

Answer 26

how atoms are connected, without drawing bonds example: Ethanol = CH₃CH₂OH

Question 27

Naming organic compounds

Answer 27

1 - meth 2 - eth 3 - prop 4 - but 5 - pent 6 - hex 7 - hept 8 - oct

Question 28

Alkane naming

Answer 28

- ane

Question 29

Alkene naming

Answer 29

- ene

Question 30

Haloalkanes

Answer 30

- alkanes with halogen atoms - 1-bromopropane (C₃H₇Br)

Question 31

Alcohols

Answer 31

-OH group - name ends in 'ol'

Question 32

Carboxylic Acids

Answer 32

- COOH group - name ends in 'oic'

Question 33

chemical + physical properties: alkanes

Answer 33

functional group: none (single bonds) chemical reactions: combustion reaction physical: increases w/ number of carbon molecules

Question 34

chemical + physical properties: alkenes

Answer 34

functional group: C=C (double bonds) chemical reactions: addition reaction physical: increases w/ number of carbon molecules

Question 35

chemical + physical properties: alcohols

Answer 35

functional group: -OH (hydroxyl) chemical reactions: oxidation physical: increases w/ number of carbon molecules

Question 36

chemical + physical properties: carboxylic acids

Answer 36

functional group: -COOH (carboxyl) chemical reactions: - physical: - increases w/ number of carbon molecules - decreased in solubility

Question 37

Biomass

Answer 37

any natural material from living things that can be used as fuel or for making energy INCLUDES: plant-based materials and everyday organic waste

Question 38

Plant-based biomass

Answer 38

- wood - algae - straw and grass cuttings

Question 39

Every day waste (organic waste)

Answer 39

- food waste (peels) - paper + cardboard - animal manure

Question 40

Esters

Answer 40

a condensation reaction: Alcohol + Carboxylic acid → Ester + Water

Question 41

How to name esters

Answer 41

1.) First part (alkyl): comes from the alcohol → e.g. ethanol → ethyl 2.) Second part (anoate): comes from the acid → e.g. ethanoic acid → ethanoate example: Methanol + Propanoic acid → Methyl propanoate