whizz bang summary. 2 of 35© boardworks ltd 2008 all substances are made of tiny particles called...
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Whizz BangWhizz BangSummary
2 of 35 © Boardworks Ltd 2008
All substances are made of tiny particles called atoms.
Many substances are made up of different types of atoms.
iron, aluminium, silicon, oxygen and boron atoms
carbon, nitrogen, hydrogen, oxygen and sulfur atoms
hydrogen and oxygen atoms carbon and hydrogen atoms
All substances are made of atoms
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Element or compound?
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Match the element
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How are the elements arranged?
The elements in the periodic table are arranged in families called groups and periods. A group is a vertical column in the periodic table; a period is a horizontal row.
For example, all the elements in group 0 are very unreactive gases at room temperature, while all the elements in group 1 are very reactive metals.
The elements in groups tend to have similar properties.
groups 0 to 7p
erio
ds
1 to
6
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Metals in the periodic table
Metals are on the left and in
the centre.
Non-metals are mostly
on the right.
The periodic table is a list of all the known elements, arranged according to similarities in their properties.
Where are metals and non-metals located in the periodic table?
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Properties of metals – experiment
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The right metal for the job
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Why recycle?
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The atoms in some elements join together to make molecules.
Molecules of elements
One of the elements that exists like this is hydrogen.
Each hydrogen atom joins up with one other atom to make a hydrogen molecule.
The formula of a hydrogen molecule is H2.
Other elements such as nitrogen, oxygen, and chlorine also exist as molecules. What are the formulae of these elements?
= hydrogen atomhydrogenmolecule
=
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When two or more elements react in a chemical reaction, the atoms do not just mix together, they become joined to one another to make compounds.
Atoms joining to make compounds
In a chemical reaction, the atoms in the reactants become joined in different ways and this is how
new compounds are formed.
hydrogen oxygen water+
+
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Making a compound – magnesium oxide
Magnesium oxide is produced from the reaction between magnesium and oxygen.
Two atoms of magnesium react with one molecule of oxygen to make two molecules of magnesium oxide.
What are the differences in the properties of magnesium, oxygen and magnesium oxide?
magnesium oxygen magnesium oxide+
+
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What does a formula show?
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The reactivity series
Combining the information from all the reactions gives an overall order of reactivity called the reactivity series.
One way to remember this order is to learn this silly sentence:
pleasesend
charlie’smonkeys
andzebras
inlargecages
securelyguarded!
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Order of reactivity with acid
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Investigating reactivity with oxygen
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Investigating reactivity with water (I)
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What is needed for iron to rust?
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Preventing rust
Rusting destroys a huge amount of iron and steel every day.
People spend a lot of money making sure that their iron and steel buildings, engines, lorries and ships do not rust.
What methods could you use to prevent things rusting?
painting plastic coating
oilinggalvanising
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Explaining displacement reactions
The reactivity series can be used to predict if a metal will react with a metal compound. If the metal is more reactive than the metal in the compound, it pushes out, or displaces, the less reactive metal from its compound.
If the metal is less reactive than the metal in the compound, it will not compete and so there is no reaction.
more reactive
metal
lessreactive metal
compound
morereactive metal
compound
less reactive
metal+ +
less reactive metal
more reactive metal compound
no reaction+