Periodic Table, Reactivity, and Polymers

Alkaline metals

Alkaline metals

Group 1 elements on the periodic table

Alkaline earth metals

Group 2 elements on the periodic table

Halogens

Group 7 elements on the periodic table

Noble gases

Group 8 elements on the periodic table with full outer shells

Transition metals

Elements in the middle chunk of the periodic table

Group 8

Elements on the far right-hand side of the periodic table

Full outer shell

Characteristic of noble gases, making them unreactive

Uses of noble gases

Helium in balloons and neon lights

Halogens

Nonmetals that go around as diatomic molecules

Reactivity of halogens

Highly reactive, wanting to gain one electron

Boiling point of halogens

Changes as you move down the group

Halogens and group one metals

Halogens react violently and rapidly with group one metals

Displacement reactions

More reactive element displaces a less reactive element

Uses of halogens

Mostly used for sterilizing things

Reactivity of halogens

Most reactive at the top due to least shielding

Alkali metals

React violently with water

Uses of alkali metals

Produce flames and different colors, used in fireworks

Storage of alkali metals

Kept in oil to prevent reaction with oxygen or water

Reaction of alkali metals with oxygen

Forms metal oxide

Reaction of alkali metals with water

Forms metal hydroxide, releasing heat and hydrogen gas

Reactivity of alkali metals

Highest at the bottom and lowest at the top

Shielding and reactivity

Alkali metals at the bottom are the most reactive due to more shielding

Measuring the rate of reaction

Using units such as cm³/min or g/s

Graphs for rate of reaction

Volume of carbon dioxide produced and mass lost

Finding rate at a specific point

Drawing a tangent line on the graph and calculating its gradient

Variation in rate of reaction

Different points in the reaction have steep or shallow tangents

Color change in reaction

Indicates rate of reaction, from clear to opaque

Safety precautions in reactions

Avoiding contamination, temperature control, and hand protection

Gas collection in reactions

Using an inverted measuring cylinder and delivery tube

Factors affecting rate of reaction

Size of reactant particles and temperature

Dissolution of sugar cubes

Demonstrates effect of temperature on rate of reaction

Rate of reaction and temperature

Faster at higher temperatures due to increased particle energy and movement

Surface area and rate of reaction

Larger surface area leads to more available particles for reaction

Pressure or concentration and rate of reaction

Higher pressure or concentration increases likelihood of successful collisions

Catalysts

Lower activation energy of a reaction

Endothermic reactions

Absorb energy and feel colder

Exothermic reactions

Release energy and feel hotter

Calculating energy change in reaction

Considering bond energy breaking and making

Balanced equations

Necessary to calculate energy change in a reaction

Balancing a chemical equation

Ensuring equal number of atoms on both sides

Drawing a balanced equation

Using coefficients to represent the number of each molecule

Notation of bonds in equation

Representing bonds between atoms

Bond energies

Given in the exam to calculate energy of reactants and products

Calculating energy change

Multiplying bond energies by number of bonds and subtracting products from reactants

Negative sign in energy change

Indicates exothermic reaction

Crude oil

Mixture of different length hydrocarbons

Fractional distillation

Separating crude oil into different components based on boiling points

Flammability of hydrocarbons

Short hydrocarbons are more flammable, long hydrocarbons are more viscous

Cracking of hydrocarbons

Using heat and catalyst to break long hydrocarbons into short alkanes and alkenes

Complete combustion of hydrocarbon

Involves lots of oxygen, produces water and carbon dioxide

Incomplete combustion of hydrocarbon

Insufficient oxygen, produces water, carbon dioxide, carbon monoxide, and carbon

Dangers of carbon monoxide

Highly toxic and suffocating

Greenhouse gases

Carbon dioxide, water vapor, and methane

Global warming

Effects include melting ice caps, increased flooding, rising sea levels

Impact of global warming

Climate change, shifting habitats and food sources

Carbon footprint

Measure of carbon emissions from daily activities

Factors affecting carbon footprint

Transportation mode, food choices, human activities

Contributions to carbon dioxide production

Burning fossil fuels, deforestation, reliance on petrol cars

Predictions for increasing carbon dioxide levels

Leading to global warming

Sulfur dioxide

Major pollutant that dissolves in clouds and causes acid rain

Effects of acid rain

Negative effects on animals, plants, and structures like limestone statues

Carbon in the air

Leads to smog and global dimming

Water vapor

Contributes to global warming

Carbon monoxide

Toxic gas

Nitrogen oxides

Contribute to smog and acid rain

Alkanes

Hydrocarbons with single bonds only

General formula for alkanes

Cn H2n+2

Examples of alkanes

Methane, ethane, propane, butane

Alkenes

Hydrocarbons with a double bond

General formula for alkenes

Cn H2n

Examples of alkenes

Ethene, propene, butene, pentene

Testing alkenes

Using bromine water, which turns from orange to colorless

Pentane

Complete combustion of hydrocarbon with lots of oxygen

Incomplete combustion of pentane

Produces carbon monoxide, highly toxic and suffocating

Carbon in incomplete combustion

Creates black soot

Condensation polymerization

Adding monomers together, losing a water molecule

Functional groups in condensation polymerization

Present at opposite ends of amino acids

Thermosetting polymers

Have cross-links, slide past each other upon heating

Thermosoftening polymers

Cannot slide past each other, melt instead

Structured DNA

Double helix structure with bases A, T, C, and G

Sugar-phosphate backbone

DNA strands held together by sugar-phosphate bonds

Genes in DNA

Sections containing information for making amino acids and proteins

Alcohols

Compounds with -O-H functional group, end in -ol

Different alcohols

Have different numbers of carbon atoms

Uses of alcohols

Drinking or as solvents

Reactions of alcohols

Fizz with sodium, burn with oxygen, dissolve in water

Fermentation

Process to produce alcohol using sugar and yeast

Carboxylic acids

Functional group with carbon double bonded to oxygen and alcohol group

Different carboxylic acids

Have different numbers of carbon atoms

Ethanoic acid

Vinegar, reacts with carbonates to produce fizz

Reactions of carboxylic acids

Produce esters when reacting with alcohols

Nanotechnology

Rearranging atoms into specific locations and sizes

Size of nanotechnology

Much smaller than traditional technology

Properties of smaller objects

Different properties and behaviors

Applications of nanotechnology

Communication, drug delivery, personalized medicine

Concerns about nanotechnology

Wary due to its newness

Glass

Made mostly of silicon dioxide

Ceramics

Contain silicon