Reaction of Acids
• Light a Bunsen Burner and adjust it to give a YELLOW
flame.
• Add about 2ml of dilute hydrochloric acid to a test tube
and add a few drops of universal indicator:

Record the pH
• Add a piece of magnesium to the acid. To trap the gas
released, hold your thumb over the mouth of the test
tube until the pressure builds.
• Your partner will light the SPLINT with the Bunsen
burner and hold it over the test tube QUICKLY after
lifting your thumb off releasing gas.
• See page 251 to answer questions
• Make a table to record your data.
Word equations
When a reaction occurs, we write the reactants,
then an arrow followed by the products.
In an acid reaction with metal

Acid + Metal-->Salt + Hydrogen gas
E.g. Hydrochloric acid + Magnesium ->Magnesium Chloride (salt) + Hydrogen gas.
If an acid reacts with a metal bubbles of
hydrogen and a salt are made.
Salts
Salts are a large group of compounds.
Salts can be recognised by their chemical
formulae.
E,g,

Sodium
Metal name
Or Ammonium
Chloride
Non Metal name (S, O, Cl)
Or a radical (NO3, SO4,
PO4, CO3, HCO3)
Acid reactions
When acids react they make new
compounds with predicable names. These
new compounds are called salts
Hydrochloric acid: HCl, (H+ , Cl-)

This acid makes CHLORIDES
Sulfuric Acid:

H2SO4 (2H+ , SO42-)
This acid makes SULFATES
Nitric Acid: HNO3 (H+ , NO3-)

This acid makes NITRATES
Questions
Write a word equation for the reactions
you performed today (assuming they all
reacted).
Suggest why pH increases during the
reaction.
What happens to the chloride ions after
the hydrogen gas is made?
Read the LEFT side of page 253
and answer the questions
1)
2)
3)
4)
5)
6)
7)
In yesterdays experiment we reacted HCl and H2SO4 with
zinc, and noticed some bubbling but the reaction didn’t give off
a squeaky pop like it did with magnesium.
Explain why in terms of reaction rate?
How could you speed up the rate of reaction of a dilute acid?
What is the general equation for metals and dilute acids?
How are the different salts named?
What is the most common salt?
Write an equation showing the reaction to form this salt
What are some other examples of salts and their uses?
Experiment
Copper Carbonate + Sulfuric acid 
Copper Sulfate + Water + Carbon dioxide.
CuCO3 + H2SO4  CuSO4 + H2O + CO2
We can identify Carbon dioxide gas as it
turns limewater cloudy or puts a burning
flame out.
The acid turned the green powder blue
and the boiling tube began to bubble.
Acids Reacting with Carbonates.
Limestone, marble, washing soda, baking soda
are all CARBONATES.
Acids dissolve them with bubbles of gas being
made.
General Equation: Acid + Carbonate  Salt +
Water + Carbon dioxide.
E.g. Sodium Bicarbonate + Hydrochloric acid 
Sodium Chloride + Water + Carbon dioxide.
NaHCO3 + HCl  NaCl + H2O + CO2
Complete these and write the word
formula for each.
HCL + CaCO3  _____ + _____ + _____
HCl + Na2CO3  _____ + _____ + _____
H2SO4 + CaCO3  ____ + ____ + ____
NaCO3 + H2SO4  ____ + ____ + ____
Big Bang experiment
Protons will be fired through a 17-mile tunnel under Switzerland and be
made to smash into each other.
The first beam has completed its maiden journey through the Large Hadron
Collider (LHC) without incident.
The flashing of two white dots on a computer screen indicated that the
protons had reached the final point of the world's largest particle
accelerator.
This prompted a cheer and the popping of champagne corks - but there was
still a long way to go.
Scientists fired up the second beam of protons - one of the building blocks
of atoms - several hours later.
Its journey, which runs in the opposite direction to the first beam, also went
off without a hitch.
The experiment is aiming to capture an image of the conditions that existed
a billionth of a second after the Big Bang.
Physicist Dr Alan Barr, who is also in Geneva working on the project, told
Sky News: "The atmosphere is absolutely electric. Things have gone really
smoothly."
Questions – Neutralisation pg 254
1) What causes the intense pain from a jellyfish sting?
2) Describe 2 reasons why they wouldn’t use a strong
acid to neutralise the jellyfish sting.
3) Why wouldn’t you use vinegar for a wasp sting.
4) What should you do if you don’t know what has bitten
you?
5) Write the word equation for a neutralisation reaction.
6) Why do people add lemon juice to their fish?
7) Describe what indigestion is.
8) Extension: Write the word and chemical equation for
the reaction of stomach acid and indigestion tablets
containing magnesium hydroxide.
Answers
1) A basic substance in their sting.
2) -Because a strong acid may harm you
-No-one brings strong acid to the beach!
3) Because both wasp stings and vinegar are acidic
4) Treat the sting with ice
5) Acid + Base  Salt + Water
6) Because lemon juice neutralises the basic amines in
fish giving a more pleasant smell.
7) Pain from your stomach from it being too acidic, after
eating too much or too quickly.
8) -Hydrochloric acid + Magnesium Hydroxide  Water
+ Sodium Chloride
-2HCl + Mg(OH)2  2H20 + MgCl2
Neutralisation
The reaction between an acid and a base is
called NEUTRALISATION
The general reaction is:

Acid + Base  A Salt + Water
The salt is in the solution after the reaction has
finished. It can be seen if the water is
evaporated.

E.g. H2SO4 + NaOH  Na2SO4 + H2O
Sodium Sulfate is the salt
In neutralisation the H+ from the acid react with
OH- from the base to form H20!
Counting the number of atoms
When there is a small subscript number it refers
to the amount of atom before the number.

E.g H20 suggests 2 hydrogen atoms + 1 Oxygen
atom. (2 + 1 = 3 atoms)
If brackets are present, the small subscript
number refers to all the atoms in the brackets

E.g. Ca(OH)2 suggests 1 calcium atom and 2
Oxygen and 2 Hydrogen atoms. 1 + 1 + 2 = 5 atoms
When there is a large number before a formula
then it refers to the whole compound.

E.g. 2NaOH suggests 2 sets of (1 Sodium, 1
Oxygen and 1 Hydrogen). 2x(1+1+1)=6 atoms
How many atoms are there in?
1) He
3) CO2
5) NH3
7) CuSO4
9) 3H2O
11) Ba(OH)2
2) O2
4) H2
6) KCl
8)H2SO4
10) K2CO3
12) 2Zn(NO3)2
Answers
1) He = 1
3) CO2 = 3
5) NH3 = 4
7) CuSO4 = 6
9) 3H2O = 9
11) Ba(OH)2 = 5
2) O2 = 2
4) H2 = 2
6) KCl = 2
8)H2SO4 = 7
10) K2CO3 = 6
12) 2Zn(NO3)2 = 18