Chapter 5,6,24 -bonding and polymers Flashcards
What happens in ionic bonding?
Electrons are transferred from one atom to another
What happens in covalent bonding?
When atoms share electrons
Which type of bonding produces a charged atom?
Ionic bonding
What type of atoms does covalent bonding occur between?
Two non metals
What type of atoms do ionic bonds form between?
A metal and a non metal
What is a positive ion called? What about a negative ion?
Positive is a cation, negative is an anion
What are ionic lattices? What are they held together by?
Ionic lattices are made of tightly packed ions forming a 3D structure. They are held together by electrostatic forces
What are electrostatic forces?
The force of attraction between positive and negative atoms
Name the ion formula for Hydroxide, carbonate, sulfate, nitrate and phosphate?
OH-, CO3 2-, SO4-, NO3- and PO4-
What is the name for an atom being stable and having a full outer shell? It has …
Noble has configuration
What is the valency of an element?
The combining power of an element, related to the number of electrons on its outer shell, the bonds / electron transfers it has to make to become stable, 8 electrons on outer shell. So group 4 would be 4, 3 would be 3, 6 would be 2, etc
Give some examples of simple covalent compounds
H2 O, CO2, N2, Cl2, NO(nitrogen oxide) NO2(nitrogen dioxide)
In what state can ions only conduct?
Ions can only conduct in liquid as they are free to move
Give some examples of properties of ionic bonding
They are brittle, conduct when free to move in a liquid, have high melting and boiling points, solid at room temperature
What are intermolecular forces?
Forces between molecules
Are intermolecular forces weak?
Yes. That’s why molecules separate easily and have a low melting point
What are the bonds that hold covalently bonded atoms together? Are they strong or weak?
Strong covalent bonds hold the atoms together
Why are simple covalent bonds liquid or gas at room temperature?
The intermolecular forces are weak so don’t require much energy to break and have a low melting point
What are polymers?
Large molecules made of hundreds of monomers joined together in a chain
What are plastics?
Synthetic polymers that can be shaped by heat or pressure
What are monomers in a polymer joined together by?
Covalent bonds between atoms
What are monomers?
Small molecules with double bonds so they can join to form polymers
Name some properties of metals
Malleable, delocalised electrons/good conduction, high melting and boiling points, sonorous, tightly compact atoms, conduct heat
What does sonorous mean?
It makes a deep or ringing sound
What is a lattice?
A regular repeating pattern of atoms
What side of the periodic table are metals on? What does this mean for the charge of the ion made in ionic bonding?
Metals are on the left hand side of the periodic table meaning they always loose electrons so always gain a positive charge
What strong force holds delocalised electrons and positive nuclei in metals?
Strong electrostatic forces
The more delocalised electrons a metal has the higher its…
Melting point is
Name the 4 main types of diagrams and models of atoms and their bonding
Ball and stick diagram, ionic models, displayed formula, cross and dot diagrams
What is the difference between simple covalent and giant covalent?
Giant covalent have many more covalent bonds that form a lattice structure, whereas in simple covalent atoms share electrons but are held together by weak intermolecular forces
Give some examples of giant covalent structures
Graphite, diamond
Which type of bonding conduct electricity?
Ionic, as a liquid, and metallic
What are the 4 types of bonding?
Ionic, simple covalent, giant covalent and , metallic
Give some examples of ionic compounds
Sodium chloride, NaCl
Lithium Fluorine
Copper sulfate, CuSO4
Which is the only type of bonding which leaves its atoms not solid at room temperature?
Simple covalent bonding as it has a low melting point
Name some properties of simple covalent bonding
Low melting/boiling point Doesn’t conduct No overall charge Small molecules Liquid/gas at room temperature
How are metals malleable ?
They have no fixed directional bonds so they can be cut/moved into any form as they are not just in layers like lattices
Why does an the loss of an electron always form a cation?
Loss of electron means there is more positive charge as there are more protons than electrons in the atom left over
How are copper sulfate and copper sulfide different in terms of the elements they contain?
Copper sulfate contains oxygen atoms as well as copper and sulfide
Describe a physical property test you could use to tell the difference between copper sulfide (fools gold)and metallic gold
Test it’s electrical conductivity, gold metal will conduct
Suggest some reasons why graphite would be suitable in mobile touchscreens by referring to some of its properties
It’s strong as it’s held together by covalent bonds so it won’t smash easily
Smooth and malleable so can be cut into layers
Thin so it won’t add to weight of phone
Fullerenes are made of carbon. Why do fullerenes have lower melting points than graphite or graphene ?
Because the intermolecular forces in fullerenes are weaker as there are less bonds
Why does heating some molecules cause them to change state but not cause them to break apart?
They have weak intermolecular forces so molecules break apart but the bonds between atoms are strong so those don’t break apart
What element are both graphite and diamond made from? They are allotropes of …
Carbon
They are allotropes of carbon
What is an allotrope?
Different forms/ structures of the same element with different structures of molecules of that element
What are the similarities between graphite and diamond?
They are made of carbon, both solid, both giant covalent structures, strong covalent bonds
What are the differences between graphite and diamond?
Graphite has bonds with 3 cartons (carbon surrounded by 3 others) therefore has one free electron as carbon is group 4. Diamond is carbon covalently bonded with 4 carbons,
Graphite is softer
Graphite conducts electricity
Why does graphite conduct electricity? How?
Charge is able to flow through graphite as there is a free electron, as not all of the 4 electrons in some of the carbons are covalently bonded. This free electron becomes delocalised and can flow through the whole layer (the bonding layer) of the graphite
Why is diamond extremely useful and strong?
It has very very strong covalent bonds as it is in a lattice structure and has all of the electrons and atoms covalently bonded, all 4 carbons covalently bonded to another carbon. This means it is strong and can be used on the edges of drills / tools
Why is graphite soft and can be split into layers?
Graphite is soft as it is split into layers that can slide over each other, as they are only held weakly by intermolecular forces
What is Graphene ?
A layer of graphite, one atom thick and able to conduct, not a simple molecule as it can keep extending
What is graphenes lattice shape?
A one atom thick layer that keeps building / extending
What are fullerenes?
Simple molecules ( which do have a limit to how far they extend), formed from carbon and are a spherical or tube shape.
What are the properties of fullerenes ?
Low melting / boiling point, soft and slippery
Name all the allotropes of carbon
Diamond, fullerenes, graphite and graphene (one layer of graphite)
