MENDELEEV: • Arranged by atomic mass

• Similar properties • Left gaps for elements yet

to be discovered

NEWLANDS:

• Built on Dalton’s Law of Octaves ( every 8th element had similar properties)

• Arranged by atomic mass • Two elements in same box

Early Periodic Table Periodic

Table

Modern Periodic Table Periodic

Table

• Metals/Non-metals • Arranged by proton

number • Groups – number of

electrons on outer shell

• Periods – number of shells

Group 1 – Alkali Metals Periodic

Table

• Group 1 metals 1+ ion • Li, Na, K – less dense than water • Reaction with water --> make H2

• Alkali metals….metal hydroxide • Universal indicator – purple • Down group – lower mpt/bpt

• Reactivity INCREASES down the group • Larger atom • Outer electron further away from +ve nucleus • EASIER to lose due to SHIELDING effect of

other electrons • Less electrostatic force

Stored in oil, as reacts with oxygen in air

Group 7 – Halogens Periodic

Table

• Group 7 non-metals 1- ion • Coloured vapours • Diatomic molecules • Down the group – higher mpt/bpt • Forms ionic compounds with Grp1

• Reactivity DECREASES down the group • Larger atom • Outer shell further away from +ve

nucleus • HARDER to gain an electron due to

SHIELDING effect of other electrons • Less electrostatic force to attract

electron

HALOGEN DISPLACEMENT A more reactive

halogen will displace a less

reactive one from a compound

Transition Metals

Periodic Table

Compared with Group 1… •Higher mpt •Higher density •Stronger/harder •Much less reactive Used for catalysts Form coloured compounds Ions with different charges

• Similar properties because they fill

an inner 3rd shell ( 3d shell). This can hold 18 electrons, once 2 electrons fill the 4th energy level.

• Usually have same number of electrons on outer shell

Water Cycle

Water

• Water evaporates due to Sun’s thermal energy.

• Condenses to form clouds

• Precipitation ( rain/snow/sleet) occurs.

Ionic compounds are soluble, but covalent ones are not.

Hard Water

Water

Contains Mg2+ and Ca2+ ions, dissolved when water passes through rocks

+ve - Ca for

bones/teeth

-ve - Kettles furrow up less efficient

Soft water easy lather Hard water less lather

SCUM When hard water reacts with soap.

SCALE When hard water is heated.

SCALE is basically limescale which is Calcium Carbonate which is a solid ppt and forms on

metal appliances reducing efficiency.

Removing Hard Water

Water

Add Sodium Carbonate Precipitates out the Ca and Mg ions to form insoluble

carbonates

Use washing

soda

Ion Exchange

(water softener)

Filled with resin. Contain Sodium/Hydrogen Ions As the water is passed through the resin, the Na/H ions are EXCHANGED with the Ca/Mg ions. Needs to be topped up with Na ions so NaCl is poured in to replenish.

Water Treatment

Water

Distillation = PURE WATER

Made safe to drink by removing solids and micro-organisms

Carbon reduces Cl levels Ion exchange resin

Silver discourage bacterial growth on filter

Water source Filter solids

Sedimentation of small particles using Aluminium sulphate

Chlorine used to disinfect

Filter of fine sand

Periodic Table

Water

Acids & Alkalis

Energy

Analysis

C3

Strong/Weak Acids/Alkalis

Acids &

Alkalis TESTING whether strong or weak…use Universal Indicator

STRONG ACIDS fully dissociate into their ions

HCl H+ + Cl-

WEAK ACIDS partially dissociate into their ions

CH3COOH ↔H+ + CH3COO-

Same for alkalis, just OH- ions

Titration

Acids &

Alkalis Used to determine accurately how much alkali is needed to

react completely with a known volume of acid ( or vice-versa)

Phenolphthalein STRONG ALKALI and WEAK ACID

Methyl Orange STRONG ACID and WEAK Alkali

NEUTRAL – pH7

Known volume

and conc

Unknown volume

END POINT Acid-base reaction is complete

Energy from fuels

Acids &

Alkalis Energy

Calorimeter

Think HSW!

Bomb calorimeter

4.2J raises temp of 1 g of water by

1 degree

Food high in carbs and fats have lots of energy!! more than

body needs obesity

A + B C If 0.1 mole of reactants. Total mass of A and B is 100g. Temp start is 19.6, temp max is 26.1 Work out diff….6.5

(Don’t need to learn this, you would get this) So for 0.1 moles = 2730J

For 1 mole 2730 x 10 27300J (27.3kJ) …..exothermic reaction ( as temp rise) = -27.3kJ/mol

Energy change = mass x 4.2 x temp change

Energy changes

Acids &

Alkalis Energy

Reaction = bond breaking ( endo) and bond making ( exo)

EXOTHERMIC

Energy required to break bonds in less than energy released when new bonds

are formed

ENDOTHERMIC

Energy required to break

bonds in greater than energy released when new

bonds are formed

CATALYST…. Lowers activation

energy

∆H = - ve ∆H = + ve

Bond energies

Acids &

Alkalis Energy

CH4(g) + 2O2(g) 2H2O(l) + CO2(g)

Identify the bonds…..stick diagrams!

Bond Bond energy

kJ/mol

H-H 436

Cl-Cl 242

H-Cl 431

O-H 464

C-C 347

C-O 335

O=O 498

∆H = bond breaking + (- bond making)

Add up on the bonds in the reactants. This is bond energy needed to break the bonds

Add up on the bonds in the products. This is bond energy needed to make new bonds.

REMEMBER… making new bonds is an exothermic reaction…so it is always a –ve number

Positive Ions

metal flame test colour

barium apple green

calcium brick red

potassium lilac

lithium bright red

sodium orange

Acids &

Alkalis Energy Analysis

FLAME TESTS

Add Sodium

Hydroxide

Cu 2+

Fe 3+

Fe 2+

Add NaOH, gently warm. Ammonium gas turn red litmus

paper blue

Negative Ions

Acids &

Alkalis Energy Analysis

Carbonates add acid bubbles if they

turn limewater cloudy

Copper Carbonate Copper Oxide

Zinc Carbonate Copper Oxide

Halides Add nitric acid and silver nitrate

Cl Br I

White Cream Yellow

SULPHATES ( add HCl to removes any carbonate ions)

Add Barium Chloride white ppt

NITRATES

Test for ammonia first negative result Add ALUMINIUM ( this reduces the

nitrate ion to Ammonium ions) Test again for ammonia gas positive

result

Titration Calculations

2NaOH + H2SO4 Na2SO4 + 2H2O

Write what you know from the question.

V = 30cm3 Conc = ? V = 20cm3 Conc = 0.5

1. Convert vol into dm3 by dividing by 1000.

2. Calculate moles of substance of known vol and conc

Moles = Concentration × Volume

3. Look at the equation for the ratio. Here, it is 2:1 So we calculate moles of acid here and then multiply this by 2

4. Now rearrange the formula to allow you to work out the unknown

If they want you to work out the g/mol

All you do is multiply the

RFM ( they give you this!) by the

concentration you calculated

Analysis

What is ammonia?

It is made industrially by reacting

nitrogen with hydrogen in the Haber

process. It is a reversible reaction,

so it never goes to completion.

hydrogen nitrogen + ammonia

N2 (g) 3H2 (g) 2NH3 (g) +

Ammonia is an important compound

in the manufacture of fertilizer and

other chemicals such as cleaning

fluids and floor waxes.

Why is this a problem for companies

making ammonia?

What is yield? The amount of product made in a reaction is called the

yield and is usually expressed as a percentage. a

mm

on

ia y

ield

(%

)

pressure (atm)

The yield of ammonia produced by the Haber process

depends on the temperature and pressure of the reaction.

What is the Haber compromise?

In practice, though, these

conditions are not used. Why?

The highest yield of ammonia

is theoretically produced by

using a low temperature and

a high pressure.

A compromise is reached to make an acceptable yield in

a reasonable timeframe while keeping costs down.

Lowering the temperature slows down the rate of reaction.

This means it takes longer for ammonia to be produced.

Increasing the pressure means stronger, more expensive

equipment is needed. This increases the cost of producing

the ammonia.

The Haber compromise To produce a high yield of ammonia, but with a fast rate

of reaction and without the need for overly expensive

equipment, the Haber process is carried out at 450 °C

and 200 atmospheres.

The most important factor in

deciding what conditions to use is

therefore not yield, but total cost.

raw materials

equipment

energy

wages

What costs are involved in

the industrial production of

ammonia?

Maximizing productivity What else can be done to maximise productivity in the

manufacture of ammonia?

An iron catalyst is used to increase the rate of

reaction. It speeds up both the forward and backward

reaction, so the position of equilibrium is not affected.

The ammonia is cooled, liquefied and then removed

as it is produced. This causes the equilibrium to shift to

the right to produce more ammonia.

Unreacted nitrogen and hydrogen are recycled and

given another chance to react.

What is dynamic equilibrium? In some reversible reactions, the forward and backward

reactions largely occur in the same conditions and at the

same rate.

These reactions are said to be in dynamic equilibrium –

there is no overall change in the amount of products and

reactants, even though the reactions are ongoing.

Dynamic equilibrium can only take place in a closed system,

otherwise the products would escape.

reactant A

+

product reactant B

Setting dynamic equilibrium The position of dynamic

equilibrium is not always at a

half-way point, i.e. when there are

equal amounts of products and

reactants. It may be at a position

where there are mainly reactants

with a little product, or vice versa.

The position of equilibrium is influenced by two main factors:

temperature

concentration (or pressure for reactions involving gases)

Adding a catalyst speeds up the time it takes to reach

equilibrium, but does not change the position of equilibrium.

Opposing change Whenever a change is made to a reversible reaction in

dynamic equilibrium, the equilibrium will shift to try and

oppose the change.

Increasing the temperature shifts the

equilibrium in the direction that takes in heat.

Increasing the concentration of a substance

shifts the equilibrium in the direction that

produces less of that substance.

Increasing the pressure shifts the equilibrium

in the direction that produces less gas.

Temperature

Concentration

Pressure

Condition Effect

Exothermic and endothermic reactions All reactions are exothermic (give out heat) in one direction

and endothermic (take in heat) in the other.

If the temperature is increased:

If the temperature is decreased:

equilibrium shifts to decrease the temperature

equilibrium shifts in the endothermic direction

equilibrium shifts to increase the temperature

equilibrium shifts in the exothermic direction

Concentration and equilibrium Changing the concentration of a substance affects the

equilibrium of reversible reactions involving solutions.

increasing the

concentration of

substance A

equilibrium shifts to

decrease the amount of

substance A

=

decreasing the

concentration of

substance A

equilibrium shifts to

increase the amount of

substance A

=

Pressure and equilibrium Changing the pressure has an effect on the equilibrium of

reversible reactions involving gases.

If the pressure is increased:

equilibrium shifts to decrease the pressure

equilibrium shifts in the direction of fewest

molecules

If the pressure is decreased:

equilibrium shifts to increase the pressure

equilibrium shifts in the direction of most

molecules

Alcohols

What Are Alcohols? • Alcohols are organic chemical compounds which form

a homologous series. They are compounds in which one or more hydrogen atoms in an alkane (saturated hydrocarbon) are replaced by hydroxyl (OH) groups.

• The hydroxyl group (OH) is the part of the molecule that is responsible for the characteristic reactions and chemical properties of the alcohol. This is otherwise known as the 'functional group'

Ethanol

• Ethanol is an alcohol.

Ethanol can be represented in a number of different forms:

• C2H5OH

• CH3CH2OH

Facts about Ethanol

Ethanol can:

• Dissolve in water to form a neutral solution.

• React with sodium to from hydrogen.

• Burn in air.

• Be used as fuels and solvents, and is the main alcohol in alcoholic drinks.

• Ethanol can be oxidised to ethanoic acid (by chemical oxidising agents or microbial action).

So what does Ethanol look like?

• The molecular structure of ethanol looks like this:

The ‘OH’ part of Ethanol is sometimes referred to as the functional group

Methanol

• Methanol is another alcohol, which as we know, is also a member of the homologous series.

Methanol can be represented as a formula:

• CH3OH

Methanol

• The molecular structure of methanol look like this:

The ‘OH’ part of methanol is sometimes referred to as the functional group!

Facts about Methanol

Methanol can:

• Dissolve in water to form a neutral solution.

• React with sodium to from hydrogen.

• Burn in air.

• Be used as fuels and solvents, and is the main alcohol in alcoholic drinks.

Carboxylic acid

• A carboxylic acid is an organic acid that contains one or more carboxyl groups. They usually have higher boiling points than water and are usually quite weak acids. These longer chain acids tend to be rather soluble in less-polar solvents such as ethers and alcohols.

Ethanoic Acid

• Ethanoic acid can be found in your kitchen, any ideas? Yes, its vinegar! Ethanoic acid is one of the simplest carboxylic acids.

The ‘COOH’ part of ethanoic acid is sometimes referred to as the functional group

Facts about Carboxylic acids

Carboxylic acids: • Dissolve in water to produce acidic solutions. • React with carbonates to produce carbon dioxide. • React with alcohols in the presence of an acid

catalyst to produce esters. • Do not ionise completely when dissolved in water

and so are weak acids. • Aqueous solutions of weak acids have a higher

pH value than aqueous solutions of stronger acids with the same concentration.

Esters

• Esters are chemical compounds made by condensing acids with alcohols. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones.

Making an Ester

• Ethyl ethanoate is synthesized in industry mainly via the classic Fischer esterification reaction of an ethanol (alcohol) and a ethanoic acid (carboxylic acid). This mixture converts to the ester in about 65% yield at room temperature:

CH3CH2OH + CH3COOH ⇌ CH3COOCH2CH3 + H2O

• The reaction can be accelerated by acid catalysis and the equilibrium can be shifted to the right by removal of water.

What do esters look like? -Ethyl ethanoate-

• Ethyl ethanoate is the organic compound with the formula CH3COOCH2CH3. This colourless liquid has a characteristic sweet smell and is used in glues, nail polish removers, decaffeinating tea and coffee, and cigarettes.

The ‘COO’ part of ethyl ethanoate is sometimes referred to as the functional group!