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.