Bonding,structure And Properties Of Matter Flashcards
What are solids
Particles of atoms of a substance that is tightly owcked together and vibrate in fixed positions
Properties of solids
Fixed shape and volune
Lowest energy form of matter
Held by strong forces of attraction
Vibrate
What are liquids
Made up of randomly arranged particles of a substance that is free to move around.
Properties of liquids
No fixed shape but a fixed volume
No orderly arrangement
Partciles still close together
What are gases
A state of matter where its particles are able to move around freely and spread out.
Properties of gases
Mostly empty space, distance between particles
No fixed shape or volume
No order in particle arrangement
Highest energy state of matter
Four main ways substances can change
Melting,boiling,condensing and freezing
What is melting
Solid is heated up to its melting point, particles will gain enough energy to overcome the forces between them and break out its solid arrangement
What is boiling
Liquid is heated up to its boiling point. The particles will gain enough energy to overcome the remaining forces between them and the structure of the liquid will seperate
What is condensation
In condensation gas cools down to the condensation point and looses energy, changing from a gas to liquid
What is freezing
Freezing is when a liquid cools down to its freezing point as it loses energy, changing from a liquid to solid state
Limitations of particle theory
Doesn’t consider the forces between molecukes
Assumes that all particles are spheres,doesn’t account for complex molecule shapes
Assumes all spheres are solids and inelastic, doesn’t reflect atoms,ions and molecules
What are ions
An atoms or a group of atoms that has an electric charge
How are ions formed
When atoms gain or lose one or more electrons to form a charged particle.
How are positive ions formed
Loss of electrons from the outermost shell
What are positive ions always
They are always metals as they tend to lose electrons in its outermost shell
What are negative ions
Formed by the gain of electrons in the outermost shell
What are negatives almost always
They are almost always non-metals elements as they tend to have outer shells which need to gain electrons
How are ionic bonds formed
Metal elements react with non-metal element to create a full outer shell for both elements
Ions are oppositley charged meaning there is a strong electrostatic attraction between them
What is a giant ionic lattice
Giant: very large containing milliions of ions held by many bonds
Ionic: The particle that makes up the solid are ions,each with posiitve and negative charge
Lattice: Orderly structured and made up of repeating patterns.
Properties of giant ionic lattices
Incredibly high melting points as a result of strong electrostatic attractions between oppositley charged ions. Requires lots of energy to break
Ionic solids easily soluble in water. The electrostatic attractions between the ions in the lattice and water molecules is stronger than between ions in the lattice
Ionic substances don’t conduct electricity when solid, this is due to ions in the lattice are fixed
Ionic substances will conduct when molten. When in the liquid state is ions are able to move around and as such carry a charge
What are covalent binds
Strongs bonds formed between 2 or more atoms that are both non-metals elements
How are covalent bonds formed
Covalent bonds form when two or more atoms of non-metal elements come together to form a molecule (one or more pair of electrons are shared)
Dot and cross advantages/limitations
Line diagrams advantages/limitations
3 dimensional models advantages/limitations
Allows us to visualise how electrons are shared and which atoms they orginated from however does not tell us about the shape
Line diagrams can tell us more about the
2D shape of a molecules but fail to represent the space filled by atoms
Three dimensional models shows accurate shapes of molecules and the spaces filled by their constituent atoms. We lose info e.g the distribution of electrons within the molecule.
Properties of simple covalent molecules
Bond between atoms are strong and difficult to break but the forces between the molecules are very weak
Weak intermolecular forces much easier to overcome than strong electrostatic forces of attraction
Covalent conpounds don’t conduct electricity as there are no charged particles ( balanced charges)
What are polymers
Type of covalent molecule, made up of long chains of carbon, held by covalent bomds
Properties of polymers
Stronger covalent bonds then simple covalent molecules however its intermolecular forces are still weaker than the electrostatic attractions found in ionic solids
Properties of giant covalent structures
Made up if many covalent bonds making it very strong and hard
Lots of energy required to break it down (force)
Very high melting point
Graphite : explain the structure and properties
Each carbon atom is bonded to 3 other atoms. Carbon atom with 3 electeons with a free delocalised electron. Carbon atoms arranged in flat sheets of connected hexagons
Delocalised electrons allow graphite to conduct electricity
Strong covalent bond= difficult to break (high melting point)
Weak intermolecular forces hold the sheets of strong graphite layers can slide over each other (slippery)
Graphene: explain structure and properties
Singular layer of graphite
Light material (only 1 atom thick)
Many strong covalent bonds= very strong material
Graphene has a high melting point
Graphene can conduct electricity (delocalsied electrons)
Fullerenes: explain structure and properties
Buckminsterfullerene is a hollow ball made up of 60 carbon atoms
Used for drug delivery
Carbon nanotubes are long hollow cyclinders made up of carbon atoms.
Excellent lubricants
Good conductors of electricity
What can the giant covalent structures be used for and why
Graphite: layer of graphite can slide off the tip of the pencil onto the page
Graphene: Used in composites to make other materials stronger and electronics
Buckminsterfullerene: electronic applications
Carbon nanotube: They are used to deliver deugs inside the body or as a catalyst for chemical reactions
What is metallic bonding
Metallic bonding is the electrostatic attraction between positive metal ions and delocalised electrons.
Properties of metals
Electrostatic attractions is very strong and requires lots of energy to overcome.
Metals have a high melting point
Metals are able to conduct electricity and heat easily when solid (delocalised electrons move freely)
Very ductile (metal ions can slide over each other) arranged in layers
Metal not soluble in water. Attraction between the positive metal lattice and negative sea of electrons much stronger between ions and water
Diamond: explain structure and properties
Giant structure made up of carbon atoms with 4 covalent bonds
Diamonds are hard
They have a high melting point
No electricity conducted (no delocalised electrons)
How are alloys created and why
Pure metals are too soft and may be required for certain jobs this can be done through creating an alloy
Alloy-mixture of 2 or more metals. They are usually harder due to the difference size atoms in the metal layer which distorts it thus making it more useful then pure metals.
What are nano particles
Very small particles 1 and 100nm in size
Fetaures and use of nanoparticles
SA:V increases by factor of 10
Some may conduct electricity
Used as a catalyst due to high SA
Healthcare such as polymers (masks), drug delivery vehixles
Development of tiny cirucits-some can conduct electricity
What is the structure and properties of sodium chloride
Structure: 3 dimensionsl lattice, regular repeated patterns of positive sodium ions and negative chloride ions
Properties: large amounts of energy required to overcome electrostatic forces of attraction, high melting and boiling point. They can conduct electricity when melted or dissolved in water.
