Investigating Gas Production in Chemical Reactions
Name
Aim: To calculate the mass of gas produced in a chemical reaction between vinegar and sodium
bicarbonate
Materials:
2 x 100 mL flask
Sodium bicarbonate
Vinegar
Balloon
100 mL measuring cylinder
Funnel
Ruler
Scales +/– 0.1 g
Ice-cream container or
other large collection vessel
Weigh boat
Procedure Part A:
1.
2.
3.
4.
5.
6.
7.
8.
Blow up the balloon several times to stretch it.
Use a funnel to add 1 spoonful of sodium bicarbonate to the balloon.
Fill the flask with 50 mL vinegar using the measuring cylinder.
Without allowing any sodium bicarbonate to fall onto the flask, carefully secure the opening
of the balloon around the mouth of the flask.
Place the flask on the scales and record the starting mass.
Carefully tip the balloon up so that all of the contents fall into the vinegar. Hold the base of
the balloon securely to the neck of the flask.
Once the reaction has finished, record the mass of the flask with the balloon still attached.
Now use a string and ruler to measure the diameter of the balloon. Record the diameter.
Mass before reaction (g)
Mass after reaction (g)
Diameter of balloon (cm)
Procedure Part B:
1.
2.
3.
4.
5.
6.
Fill a 250 mL flask to 100 mL with vinegar.
Measure out 1 tablespoon of sodium bicarbonate on a weigh boat.
Weigh both flask and weigh boat and record the starting mass.
Place the flask inside the ice-cream container (to catch any spillage).
Carefully add the sodium bicarbonate.
If there is any spillage in the ice-cream container, carefully pour the contents back into the
flask.
7. Reweigh the flask.
Mass before reaction (g)
(Flask + vinegar + sodium bicarbonate)
Mass after reaction (g)
Find the change in mass for Part A and Part B.
Part A
Part B
Find the volume of gas collected in the room by using the following formula:
Volume
r=radius of sphere
Diameter / 2 = radius
Group
Volume of gas in balloon
Change in mass Part A
Change in mass Part B
Average
Discussion:
1. How did you results compare to the average results?
2. What were some of the errors associated with this experiment? How could they be minimised?