Post on 16-Dec-2015
Topic: Chemical Reactions
Essential Question: What pieces of evidence indicate a chemical reaction has taken place?
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Chemical Reactions• Involve a change in the chemical
composition of substances
• Something new has been formed so it is not possible to get back the original substances.
• For example, can you take an egg that is cooked, and turn it back to a raw egg?
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Chemical ReactionsChemical equations are used to show what
happens to the elements during a chemical reaction
CH3COOH + NaHCO3 H2O + NaOCOCH3 + CO2
Reactants Yield Products
Vinegar Baking Soda
WaterCarbon Dioxide
SodiumAcetate
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred1.) Gas bubbles
For example:Baking soda andvinegar
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred2.) Temperature change
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred3.) Odor (smell) is produced
For example:When food goes bad, it produces a smell
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred4.) A change in color
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred5.) A precipitate (solid) is formed
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred6.) Heat is produced
Now take some time…
• Take 2 minutes to go over your notes and highlight or underline the main ideas that answer the essential question, you should not highlight everything:
Time to use the left hand column
• You will now write your own questions using the question starters provided.
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Chemical ReactionsInvolve a change in chemical
composition in substances It is not possible to get back your
original substances as something new has been formed.
For example: can you take an egg that is cooked, and turn it back to a raw egg?
Write a question using one of these question starters:
How would you explain…?
What is…?
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Chemical ReactionsChemical equations are used to show what
happens to the elements during a chemical reaction
CH3COOH + NaHCO3 H2O + NaOCOCH3 + CO2Vinegar Baking
Soda
WaterCarbon Dioxide
SodiumAcetate
Write a question using one of these question starters:
How is…?
What is…?
Topic: Chemical ReactionsEssential Question: What pieces of evidence indicate a chemical reaction has taken place?
Evidence a chemical change has occurred1.) Gas bubbles2.) Temperature change3.) Odor produced4.) Color change5.) Precipitate (solid) is formed6.) Heat is produced
Write a question using one of these question starters:
How do you know…?
List the…?
Now let’s write a summary
Look at each question you wrote on your own, and answer each question in a complete sentence.