Year 9 Chemical Reactions - For additional resources visit: http://www.iheartscience.net

1. Chemical Reactions
Sarah Jones
www.roligaprylar.se

2. Chemical Equations

3. Law of Conservation of Mass
Antoine Lavoisier discovered the Law
of Conservation of Mass.
http://www.unit5.org/chemistry/Equations.html
http://en.wikipedia.org/wiki/Law_of_conservation_of_mass
The total mass of the reactants or
starting materials must be equal
to the mass of the products.

4. Meaning of Chemical Formula
http://www.unit5.org/chemistry/Equations.html

5. Showing States
(s) Solid (l) Liquid (g) Gas (aq) Aqueous
http://www.unit5.org/chemistry/Equations.html

6. http://www.unit5.org/chemistry/Equations.html

7. http://en.wikipedia.org/wiki/Chemical_equation

8. http://www.unit5.org/chemistry/Equations.html

9. Endothermic Reactions
• Need energy to proceed and get their energy
from their surroundings.
• Chemical cold pack – when the chemicals
inside react they absorb energy from their
surroundings – cooling them down.
chemicalrecipes.blogspot.com

10. Exothermic Reactions
• Release energy
• The reactants have more energy than the
products.
• Energy is usually released as heat and/or light.
en.wikipedia.org

11. Combustion Reactions
• Exothermic
• When something reacts with oxygen gas –
burning or exploding.
wall.alphacoders.com

12. Pollution and Climate Change
jurnalpedia.com

13. Corrosion Reactions
• Chemical reactions that breaks metals down
to form other compounds.
www.european-coatings.com

14. Acid Reactions Acids can corrode
metals – usually form
salt and hydrogen gas.
www.nps.gov

15. Neutralisation
Reactions
Acids and bases neutralise
each other.
Acid + Base  Salt + Water
commons.wikimedia.org

16. Acids and Carbonates
Acid + Carbonate  Salt + Water + Carbon Dioxide
spmchemistry.onlinetuition.com.my

17. sco.wikipedia.org
www.syngenta.com

18. Plant Respiration
www.tvdsb.ca

19. http://mrkubuske.files.wordpress.com

20. Human Respiration
http://mrkubuske.files.wordpress.com

21. Comparing Photosynthesis and
Respiration
www.accessexcellence.org

22. www.bbc.co.uk