1. Chemical Reactions

2. How can properties of Matter change?
A physical change is when the appearance of something changes, but the molecules stay the same. This reaction CAN be reversed (not always…)
- A chemical change is when the product is different than the original substance . This change requires energy to reverse. Ie. eating food
Physical change and chemical change song

3. Physical Changes

4. Chemical Changes
Big Bang Theory

5. Evidence of Chemical Change
Colour change
Formation of a gas or solid or liquid (not a phase change!)
Energy change
Light produced
Sound
Heat gained or lost

6. Guess that type of Change
Write down your observations and classify them as quantitative and qualitative
Get ready to write down what type of change you observe

7. What’s going on?
The sugar, a carbohydrate such as C6H12O8, is mixed with the sulfuric acid, H2SO4.
The sulfuric acid dehydrates the carbohydrate removing water H2O and leaving behind carbon, C. The hot steam creates bubbles in the carbon making a carbon foam. When the foam cools it is stiff. The foam should be handles while wearing gloves since it might contain sulfuric acid.
The clouds of Venus contains sulfuric-acid-rich droplets. Carbon rich life forms should wear protective clothing when visiting Venus. Or they might experience the dehydrating effects of interaction with sulfuric acid.

8. Chemicals react based on the number of electrons they have…
Bill Nye: Chemical Reactions
Bill Nye: Kitchen Chemistry

9. Complete the handout: Chemical Change and Energy sheet.

10. Practice QUIZ
Physical, Chemical change quiz

11. Writing a Chemical Reaction
If a chemical reaction is the rearrangement of atoms to produce a new substance – there are no new atoms but there are new compounds or elements
The bonds holding the atoms together have to be broken and reformed – which can give off or absorb energy

12. Writing a Chemical Reaction
Two parts to a chemical reaction
Hydrogen + oxygen water

13. Writing a Chemical Reaction
Two ways to communicate a chemical reaction:
Word equations – use the names of the chemicals
Eg) silver + bromine silver bromide
Write an R and a P above the reactants in the equation. R P

14. Writing a Chemical Reaction
Two ways to communicate a chemical reaction:
Chemical equations – use the formulas
Eg) Ag Br AgBr
Write an R and a P above the reactants in the equation. R P

15. Worksheet to practice

16. Exothermic vs. Endothermic
Energy is released
energy is a product
Endothermic
- Energy is absorbed
- energy is a reactant

17. Grab a whiteboard
Identify the reaction as endothermic or exothermic

18. Endothermic or Exothermic
Snap bangs

19. First aid instant cold packs
Endothermic or Exothermic
First aid instant cold packs

20. First aid instant cold packs
Endothermic or Exothermic
First aid instant cold packs

21. Endothermic or Exothermic
Glucose + oxygen carbon dioxide + water + energy

22. Endothermic or Exothermic
Boiling water

23. Endothermic or Exothermic

24. Endothermic or Exothermic

25. Reactions that take in heat are called ______________
Energy is found on the _________ side of the equation
Reactions that release heat are called _____________
Energy is found on the __________side of the equation
Complete “Reactions Involving Energy” Handout.

26. Methane oxygen Combustion - any reaction that has oxygen has reactant
Types of Reactions p204,207,209,210,146,148,150,158,159, 162
Combustion - any reaction that has oxygen has reactant
Hydrocarbon combustion – substances with hydrogen and carbon react with oxygen to produce carbon dioxide and water
CH4(g) + O2(g) CO2(g) + H2O(g)
List the names of the reactants:
Methane
oxygen

27. Types of Reactions C6H12O6(s) and O2(g)
Cellular respiration – special type of HCC that occurs inside our cells in our mitochondria
Glucose + oxygen carbon dioxide + water
What is the formula for the reactants for this reaction?
C6H12O6(s) and O2(g)

28. Types of Reactions Fe(s) + O2(g) Fe2O3(s)
Corrosion – slow chemical change that occurs when oxygen in the air with water reacts with a metal
Fe(s) + O2(g) Fe2O3(s)
Only iron rusts
Other metals corrode…..
To prevent corrosion you need to protect it from the air and moisture:
Ie. galvanization – coating nails with zinc
Ie painting the nails
Ie. chromium plating
Ie. sacrificial anodes for underground fuel tanks

29. Types of Reactions A B 2) Neutralization
Acid is added to base to produce neutral products
eg) HCl(aq) + NaOH(aq) H2O(l) NaCl(aq)
Identify the acid and base in the reaction A B

30. Classify that type of reaction
Grab a whiteboard
Write out the reaction using either chemical or word equations
Identify the type of reaction
Write R and P above the reactants and products

31. Classify that type of reaction
Acid rain reacts with lime to produce water and calcium carbonate

32. Classify that type of reaction
acid rain + lime water + calcium carbonate
Neutralization R R P P

33. Classify that type of reaction
Copper on the roof of the parliament buildings turned green over time

34. Classify that type of reaction
copper + oxygen copper oxide
Corrosion R R P

35. Classify that type of reaction
Lemon juice can deactivate the smell of fish

36. Classify that type of reaction
acid rain + fish oil water + neutral product
Neutralization R R P P

37. Classify that type of reaction
Lemon juice can deactivate the smell of fish

38. Classify that type of reaction
acid rain + fish oil water + neutral product
Neutralization R R P P

39. Classify that type of reaction
Mg(OH2)(aq) + HCl(aq) MgCl2(aq) + HOH(l)

40. Classify that type of reaction
Mg(OH2)(aq) + HCl(aq) MgCl2(aq) + HOH(l)
Neutralization R R P P

41. Classify that type of reaction
CO2(g) + H2O(g) C6H12O6(s) + O2(g)

42. Classify that type of reaction
CO2(g) + H2O(g) C6H12O6(s) + O2(g) Photosynthesis (reverse combustion?) R R P P

43. Classify that type of reaction
Light hand on fire

44. Conservation of matter
Matter cannot be created or destroyed, just converted from one form to another
Antoinne Lavoisier p107
Balance chemical equations using coefficients (big number out front!)
The total mass of the reactants = the total mass of the products

45. Conservation of matter
What’s in the bag lab
Mass and Chemical Change lab p
Balance equations worksheet practice

46. Conservation of matter
If you started out with 5.6 g of baking soda and 4.9 g of vinegar, could you produce 10.5 g of carbon dioxide?
CH3COOH(aq) + NaHCO3(s) CO2(g) + NaCH3COO(aq) + H2O(l)

47. Rates of Reactions
How long it takes for reactants to form products

48. Rates of Reactions It is affected by:
Surface area – the higher the surface area, the more molecules can react
Temperature – the faster the molecules are moving, the more they collide
Concentration – the higher the concentration, the more the molecules can react
Catalyst – speed up reactions ie. enzymes
Inhibitors – slow down reactions

49. Rates of Reactions: p153-155 Changing with Time p154 #1,2 and #1-5
Coke and mentos
Rates of reaction lab - formative

50. Coke and Mentos
Low surface tension also helps bubbles grow quickly. Measurements showed that the surface tension in water containing the sweetener aspartame is lower than in sugary water, explaining why Diet Coke creates more dramatic fountains than sugary Coke.

51. Coke and Mentos
But caffeine-free Diet Coke did just as well, suggesting that caffeine does not accelerate the reaction, at least at the normal levels in the drink.
Measurements of the pH of the Coke before and after the experiments showed that its acidity did not change, ruling out the idea that a simple acid-base reaction drives the fountains.

52. Coke and Mentos
Instead, the vigour of the jets depends on various factors that affect the growth rate of carbon dioxide bubbles.
The rough, dimply surfaces of Mentos encourage bubble growth because they efficiently disrupt the polar attractions between water molecules, creating bubble growth sites.

53. Coke and Mentos Mythbusters Timewarp Our videos/demonstrations
Identify manipulated, responding, controlled variables.

54. Unit Test…
Review Bingo and
crossword