Chemistry exam 6/3/14 – Flashcards

• Positive ions surrounded by a 'sea' of delocalised electrons
• Strong attraction between ions and delocalised electrons
• High melting points
• Almost all are solid at room temperature
• Conduct electricity
• Conduct heat
• Malleable

Any metallic element has metallic bonds:

• Sodium
• Copper
• Zinc
• Sodium
• Lithium
•  Francium
• Iron
• Cobalt
• Calcium
•  Magnesium
• Silver
• Gold
• Barium
•  Platinum

and

• Chromium

are a few.

If you named at least 3 then well done.

• Regular 3D arrangement of positive and negative ions
• Strong electrostatic attraction between positive and negative ions
• High melting points
• Always solid at room temperature
• Conduct electricity when molten and in solution
• Regular crystal arrangment

• Sodium chloride
• Magnesium oxide

• Isolated molecules with weak forces between molecules
• Strong bonds between atoms, electrons are shared
• Low melting points
• Gases and liquids at room temperature
• Don't conduct electricity

• Hydrogen
• Ammonia
• Methane
• Water

• Repeating 3D structure with strong bonds between atoms
• Strong bonds between atoms, electrons are shared
• High melting points
• Always solid at room temperature
• Most don't conduct electricity (except graphite)
• Regular crystal arrangement

• Graphite
• Diamond
• Silica

CATions are positive.

Try remembering is as positive...pawsitive...pursitive...cat! And cats are great, so it's positive.

1st shell = 2 electrons

2nd = 8 electrons

3rd = 8 electrons

An atom has an equal amount of protons and electrons, and no charge.

Ions do not have an equal amount of protons and electrons, but has a full outer shell.

• Polymers are very big molecules with long chains of carbon atoms.

• Plastics are examples of polymers.

• Evidence that they could be damaging to lifeforms
• Studies have shown that nanoparticles can be toxic to animal cells
• It has been considered that exposure can cause breathing problems, and since they are small enough to be inhaled through the nose, and go straight through the nasal passage to the brain, they can cause a lot of damage there
• They can easily enter your blood stream and cause harm
• Not enough is known about them, so they are not allowed to be used

Relative atomic mass = Ar

Relative formula mass = Mr

   (Amount of product collected)   

(max. amount of product possible)

X 100 = Percentage yield

Chemicals form compounds through interacting with each other.

• Increasing the concentration of one reactant
• Increasing the temperature
• Use a catalyst