Structure, Bonding and Properties. Flashcards
What is ionisation?
When neutral atoms or molecules gets converted to charged atoms or molecules through gaining or losing electrons.
What do all atoms want and how do they achieve it?
They all want a full outer shell of electrons, they do this by forming chemical bonds with other atoms.
What are the properties of Ionic bonds?
Strong, electrostatic forces that hold ions of opposing charges together, it is described as an ionic lattice. The compounds have very high melting points.
How do non-metal atoms bond?
By sharing electrons to form a strong covalent bond.
What is an alloy?
An alloy is a mixture of a metal with another element, that have different properties to the metals that are in them.
What are the properties of an alloy?
They are less malleable than pure metals as they have irregular layers so they cannot slide over each other. The atoms are held by metallic bonding.
What is metallic bonding?
Positive ions held together by a “sea of delocalised electrons” from the outer shells of the metal atoms.
What are the properties of metal bonds?
Strong electrostatic forces between the ions and electrons, meaning high melting points, free electrons are able to move meaning they are good conductors of electricity and heat, Metals are malleable so the regular layers can slide over each other if hammered.
What are polymers?
large molecule forces that are made of repeating units (monomers). They are bonded by strong covalent bonds.
What are the properties of a giant covalent bond?
solid at room temp
held together by strong covalent bonds
need a lot of energy to break bonds.
What are the 2 examples of a giant covalent bond?
Graphite and Diamond
What is diamond made up of?
Carbon forming four covalent bonds
What is graphite made up of?
made of hexagonal rings of carbon, each atom forming three bonds.
What is graphene?
A single layer of graphite that is used to form nanotubes/fullernes.
What are the properties of graphite?
only 3 electrons from each carbon atom form strong covalent bond, leaving one delocalised electron per atom.
Graphite has a high melting point and is a good thermal/electrical conductor.
What are the properties of diamond?
Doesn’t conduct electricity - no free delocalised electron
High melting point - strong covalent bonds need a lot of energy to break.
made out of carbon.
What does a metal + a non metal form?
ionic bonds
What do 2 non - metals form?
covalent bonds
What do 2 metals form?
metallic bonds
In an ionic bond what does the metal want to do and what does the non-metal want to do?
the metal wants to lose electrons to gain a full outer shell, the non-metal wants to gain electrons to gain a full outer shell.
In a covalent bond what do the non-metals do to gain a full outer shell?
share electrons
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