React with Metals Metal Reactivity

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React with Metals Metal Reactivity

• We can use the activity series of metals to
  predict how vigorously (if at all) a metal will
  react.
• The more reactive the metal, the more vigorous
  the reaction.
• The least reactive metals do not react at all.

• Which metal fits the description silver
  potassium iron
• Explodes in acid
• Bubbles slowly in warm acid
• Doesnt react

potassium
iron
silver
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Reaction with Metals - general

• Many metals react with acids to form a salt and
  hydrogen gas.
• The general word equation is

• The salt will depend upon the metal and the acid
  used.

• Hydrochloric acid gives metal chlorides
• Sulphuric acid gives metal sulphates
• Nitric acid gives metal nitrates

• So, for example

hydrogen

magnesium chloride
?
hydrochloricacid

magnesium
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Evidence of Reaction
Some of these reactions show bubbles being
produced. These are bubbles of hydrogen gas. This
proves that a reaction is taking place because a
new substance is forming. How do we test for
hydrogen?
Oxygen in the air
hydrogen
Mg acid
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Formula of salts

• Chemists often use formula equations to show not
  just what atoms are present but also how many.
• To do this we need to understand what the numbers
  in a formula represent. Here are some examples.

Name of Salt
Contains
Formula
sodium chloride
one Cl
one Na
NaCl
magnesium chloride
two Cl
one Mg
MgCl2
potassium nitrate
three O
one N
one K
KNO3
potassium sulphate
four O
one S
two K
K2SO4
calcium nitrate
six O
two N
one Ca
Ca(NO3)2
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Activity

• How many of each type of atom does the formula of
  the salt represent?

one
two
two
one
four
one
one
four
two
one
six
one
one
four
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Formula Equations

• Step 1 Write down the word equation.
• Step 2 Replace words with the chemical formula .
  (You will be given or need to look up the formula
  at this stage.)
• Step 3 Check that there are equal numbers of
  each type of atom on both sides of the equation.
  If not, then balance the equation by using more
  than one.
• E.g. The reaction of magnesium with hydrochloric
  acid

Neither H nor Cl balance.Need 2 HCl
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Activity

• Can you finish off the equations below
• Step 1 Write down the word equation.
• Step 2 Replace words with the chemical
  formula.
• Step 3 Balance the type of atom on both sides.

Already balances No change
Need 2 K on both sides
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Metal oxides and acids
Metal oxide acid ? a salt water

• Most metal oxides are not soluble.

water

copper sulphate
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Metal oxides and acids
Metal oxide acid ? a salt water
water

zinc sulphate
water

sodium chloride
water

iron nitrate
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Metal carbonates and acids
Metal carbonate acid ? a salt
water carbon dioxide

• When metal carbonates react with acids they fizz
  giving off carbon dioxide gas.
• Most metal carbonates are not very soluble and so
  reactions may be slow.

water

calcium chloride
carbon dioxide

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Metal carbonates and acids
Metal carbonate acid ? a salt water
carbon dioxide
water

zinc sulphate
?
sulphuric acid

carbon dioxide
water

sodium chloride
?
hydrochloric acid

carbon dioxide
water

nickel nitrate
?
nitric acid

carbon dioxide