C2.1 structure, bonding and Properties

simple particle theory is developed to include atomic stucture and bonding.the arrangement of electrons can be used to explain what happens when elements react and how atoms join together. ionic, covalent and metallic bonds are strong but the forces between molecules are weaker (e.g carbon dioxide and iodine) When metals combine alloys are formed.

?
What is meant by the term 'compound?'
When two or more different atoms chemically bond to form a compound. Compounds are usually completely different to what the original elements behaviour and look. Compounds can be giant lattice structures or small molecules.
1 of 17
describe the difference between mixtures and compounds
Mixtures are easily separated- not like compounds because there is no chemical bond between the different parts of a mixture and they can be separated by physical methods such as distillation.
2 of 17
Describe ionic bonding
In ionic bonding, atoms lose or gain electrons to form charged particles called ions which are strongly attracted to one another.all the atoms on the left side of the periodic table want to lose an electron and on the right, they want to gain one.
3 of 17
Describe ionic charges
if an atom gives away an electron in order to have a full outer shell they become negatively charged and an atom that gains an electron becomes positively charged.
4 of 17
Describe ionic structures
Ionic bonds always form giant ionic structures. the ions are closely packed, have very strong chemical bonds between all the ions and have high melting and boiling points. they dissolve to form solutions that conduct electricity.
5 of 17
Describe covalent bonding
atoms share electrons so both atoms have full outer shells. hydrogen and chlorine form a single covalent bond to make hydrogen chloride. ammonia and nitrogen form three covalent bonds, methane needs four and oxygen + water can form covalent & ionic.
6 of 17
Describe the two types of covalent bonding
simple molecular substances have very strong covalent bonds which form small molecules of several atoms. the forces of attraction between these molecules is very weak so melting and boiling points are low. most are gases or liquids at room temp
7 of 17
cont.
giant covalent structures have no charged ions, bonded together with very strong covalent bonds, have high melting and boiling points and don't conduct electricity like simple structures. as they have no ions.
8 of 17
Describe metallic structures
the atoms in a metallic structure sre giant structures, and have a sea of free electrons which give metals their properties of being good conductors of heat and electricity and also being very malleable.
9 of 17
What happens when group 1 elements react with non-metals?
the element in group seven are called anions which have a negative charge and when reacted with alkali metals called cations which have a positive charge, they form ionic bonds
10 of 17
Alloys- eg carbon + iron into steel
mixtures of 2 or more metals or a metal+non-metal. because different elements have different sized atoms, the regular structure of the metal will be upset if smaller atoms are added such as carbon making it hard for the layers to slide.
11 of 17
What are memory shape alloys an example of?
they are smart materials. these behave differently depending on the conditions e.g temperature. nitino;, made from nickel + Titanium can be bent when cool and when heated will return to its original shape
12 of 17
What is meant by the term 'nanoscience'
the study of nanoparticles. these are between 1-100 nanometres in size. nanoparticles include fullerenes. these are molecules of carbon shaped like hollow balls or tubes. each carbon atom has 3 covalent bonds and can conduct electricity.
13 of 17
Describe the properties of nanoparticles
they have free electrons so are good at conducting electricity. they are very strong due to all the covalent bonds. they are made by molecular engineering which involves building or taking away molecules.
14 of 17
Describe applications of nanoscience
they can be used to reinforce graphite in tennis rackets. they have huge surface areas so can be used as catalysts.can be used to make sensors as they can detect one type of molecule such as in water purity.
15 of 17
Describe how Polymers are made
alkenes can be used to make polymers because they are unsaturated. this involves joing small alkene monomers to form large long chains of molcules called polymers. e.g polyethene
16 of 17
Describe the properties of Polymers
the properties depend on what the polymer is made from. they are affected by temperature and pressure. light stretchable polymers are used to make bags. polymers are cheap but dont break down. DNA is a polymer.
17 of 17

Other cards in this set

Card 2

Front

describe the difference between mixtures and compounds

Back

Mixtures are easily separated- not like compounds because there is no chemical bond between the different parts of a mixture and they can be separated by physical methods such as distillation.

Card 3

Front

Describe ionic bonding

Back

Preview of the front of card 3

Card 4

Front

Describe ionic charges

Back

Preview of the front of card 4

Card 5

Front

Describe ionic structures

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

C2
See all Chemistry resources »See all Structure and bonding resources »