REACTIONS OF ACIDS PRACTICAL
Aim:
To investigate some common reactions of acids.
Materials:
1.0M hydrochloric acid
1.0M nitric acid
1.0M sodium hydroxide
Solid sodium carbonate
Solid sodium hydrogen carbonate
Solid aluminium oxide
Limewater
Side arm test tube
3 x 100mL beaker
Spatula
Thermometer
Test tube with stopper
Magnesium strip
matches
Risk assessment:
RISK
LIKELIHOOD
CONTROL
HCl and HNO3 are corrosive
and cause damage to skin and
eyes
Unlikely
Wear gloves and safety glasses
NaOH is corrosive and causes
damage to skin and eyes
Unlikely
Wear gloves and safety glasses
Limewater is irritating to skin
Moderately likely
Wear gloves
Results:
Experiment number
1
2
3
4
5
What to do
Place a piece of magnesium in
a test tube with 3cm of
hydrochloric acid and stopper.
Hold the stopper on for about
a minute then test the gas
with a lit match.
Place about 10mL of
hydrochloric acid in a small
beaker and take the
temperature. Add about 10mL
of sodium hydroxide and take
the temperature again.
Place a spatula of sodium
carbonate into a small beaker
and add 10mL of nitric acid.
Record any temperature
changes.
Place a spatula of aluminium
oxide into a small beaker and
add 10mL of nitric acid. Record
any temperature changes.
Place a spatula of sodium
hydrogen carbonate into a side
arm test tube. Add 10mL of
nitric acid. Stopper the tube
and place the delivery tube
into a small beaker of
limewater.
Observations
Tube got hot; gas formed; gas
made popping sound with
match.
Temperature increased by 5°C
Temperature decreased 3°C,
gas produced, solid dissolves
Temperature increased by 4°C,
dissolution not obvious
Gas produced; makes
limewater turn white/milky
Discussion:
In the first reaction, a metal reacts with an acid to produce salt and hydrogen gas:
Magnesium + hydrochloric acid  magnesium chloride + hydrogen
General reaction: acid + metal  salt + hydrogen
Hydrogen makes a popping sound with a lit match due to this reaction:
Hydrogen + oxygen  water (+ energy)
In the second reaction, this reaction occurs:
Sodium hydroxide + hydrochloric acid  sodium chloride + water
General reaction: acid + base  salt + water
In the third reaction, nitric acid reacts with a carbonate:
Nitric acid + sodium carbonate  sodium nitrate + water + carbon dioxide
General reaction: acid + carbonate  salt + water + carbon dioxide
The fourth reaction is the reaction of an acid and an oxide:
Aluminium oxide + nitric acid  aluminium nitrate + water
General reaction: acid + oxide  salt + water
The fifth reaction is another acid/carbonate reaction, but this time the gas produced was bubbled
through limewater using a side arm test tube and a delivery tube. The limewater turned milky white.
Sodium hydrogen carbonate + nitric acid  sodium nitrate + water + carbon dioxide
General reaction: acid + hydrogen carbonate  salt + water + carbon dioxide
Limewater is a solution of calcium hydroxide. It reacts with carbon dioxide to form a white calcium
carbonate precipitate:
Calcium hydroxide + carbon dioxide  calcium carbonate + water
The only problem encountered in this task was that the limewater was already a bit cloudy to start
with, so you had to observe carefully to see the precipitation occurring.
Conclusion:
Acids react with other substances in a variety of ways.