Topic 1 - Key Concepts Flashcards Preview

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Flashcards in Topic 1 - Key Concepts Deck (46):
1

Chlorine Formula

Cl2

2

Ammonia formula

NH3

3

Ammonium ion

NH4+

4

Nitrate ion

NO3-

5

Sulfate ion

SO4 2-

6

Hydroxide

OH-

7

Carbonate ion

CO3 2-

8

Ionic equation

Symbol equation but spectator ions are removed

9

Hazard

Anything with the potential to cause harm

10

Risk

Is the probability of someone being harmed

11

Oxidising symbol

Provides oxygen which allows other materials to burn.

12

Harmful

‘!’ Cause irritation

13

Environmental hazard

Harmful to organisms and the environment

14

Toxic

Can cause death. By swallowing, breathing, contact.

15

Corrosive

Destroys materials including living tissue.

16

First atomic structure

John Dalton, everything is made up of solid spheres.

17

‘Plum pudding model’

JJ Thompson. Discovered charge and mass. He concluded there must be electrons.

18

Rutherford

Gold leaf experiment, concluded there is a positive nucleus surrounded by moving electrons.

19

Final atomic structure.

Bohr suggested energy levels with fixed orbits. Each shell has a fixed energy.

20

Relative mass of an electron

0.0005 (1/2000)

21

Relative atomic mass (Ar)

Average mass of one atom compared to the 1/12 of the mass of Carbon-12

22

Dmitri Mendeleev

Sorted into groups based on properties. He ordered using Atomic Mass. He left gaps for undiscovered elements and predicted their properties (ekasilicon and germanium). Tellurium and Iodine were the wrong way around.

23

Ionic Bonding

Metal and Non-metal react. Metal loses electrons forming a Cation. Non-metal gains electrons forming an anion. They are held together by electrostatic attraction.

24

Ionic lattice

Giant,crystalline, Strong electrostatic attraction in all directions.

25

Limitations of 2D representations (displayed formula)

Don’t show the shape or size of atoms.

26

Dot and cross diagrams limitations

Don’t show arrangement or size.

27

3D model limitations

Only show the outer layer of the substance.

28

Ball and stick limitations

Misleading with gaps between atoms where electrons interact, don’t show correct scale.

29

MP and BP of covalent substances

Low, as intermolecular are weak.

30

As molecules get bigger their..

Intermolecular forces require more energy to break them.

31

Giant covalent properties

Strong Covalent bonds.
Very high MP and BP.
Don’t conduct.
Insoluble.

32

Diamond

Each carbon is bonded 4 times. Require lots of energy to break bonds. Rigid lattice making it very hard. Can’t conduct.

33

Graphite

Each carbon bonded 3-times. The extra electron is delocalised making it conductive. Layers can move making it a good lubricant.

34

Graphene

A single layer of graphite.
Sheet of carbon hexagons.
One atom thick, 2D.

35

Fullerenes

Form molecules of carbon shaped in tubes or balls. Made up of carbon Hexagons (sometimes pentagons and heptagon).

36

Uses of Fullerenes

1. Delivering drugs to cells. ‘Cage’ other molecules.
2. Very large surface area used for industrial catalysts as molecules can be attached to them.
3. Nanotubes can be used (graphene cylinders) to strength materials as they’re strong and light

37

If mass increases

Reactant was a gas

38

If mass decreases

Product is a gas.

39

Find molecular formula from empirical formula

Find Mr of empirical formula.
Mr of compound / Mr of empirical formula

Multiply empirical formula

40

Moles =

Mass
Mr

41

Avogadro’s constant

6.02 x 10^23

42

Concentration

Mass / volume

43

1dm^3

1000cm^3

44

Empirical formula experiments.

Weigh crucible.
Add magnesium, weigh again, subtract from original to calculate the mass.
Heat the crucible with lid (preventing bits escaping) until all ribbon has turned white.
Cool and reweigh crucible with contents. Calculate the mass of magnesium oxide. Calculate moles of added oxygen and original magnesium.

45

Limiting reactant

The reaction stops once one of the reactants have been used up.

Amount of product ∝ limiting reactant.

46

Find balance equation from masses

Calculate the number of moles
Divide through by the lowest number of moles.
Make it integer. Put into equation.