chemical reactions 3-1

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What happens when you mix two substances together?

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  • 1. Focus Question: What happens when you combine different chemicals? Fizz QuizInvestigation3-1

2. Chemical Introduction

  • What do you know about these substances?
    • Citric Acid
    • Baking Soda
    • Calcium Chloride
  • Safety First!
    • Dont taste
    • Wear goggle

3. What do you remember about Solutions?

  • How can you make a solution?
  • How do you know if a mixture is a solution?
  • What does solubility refer to?
  • Do you think these three chemicals will make solutions with water?
  • How can you find out?

4. Make Solutions

  • Groups 1, 3, 5, 7, and 9 will test Baking Soda
  • Groups 2, 4, 6, and 8 will test Calcium Chloride
  • Testing Procedure:
    • Get one spoon of assigned chemical in cup
    • Add 50 ml of water to substance and stir

5. Solution Results

  • Baking soda and water make a solution
    • Needed to add 25 ml of water
    • Not as soluble as citric acid, kosher salt
  • Calcium Chloride and water make a solution
    • Property of Calcium Chloride
      • as it dissolves,energyis released in the form of heat

6. Two-Chemical Solutions

  • Know that citric acid, calcium chloride, and baking soda all form solutions when mixed with water.
  • Do you think mixtures of these substances will form solutions when they are mixed with water?
    • If you mix baking soda and calcium chloride with water, will a solution form?

7. Fizz-Quiz Place Mat

  • Place Mat will help organize your investigations.
  • Label 3 cups: 1, 2, and 3
  • Different pair of substances in each cup
    • Cup 1: Calcium Chloride and Baking Soda
    • Cup 2: Calcium Chloride and Citric Acid
    • Cup 3: Baking Soda and Citric Acid
  • Once substances are made, set them on the corresponding circle on Fizz-Quiz place mat

8. Fizz-Quiz Observation Sheet

  • Record your observation using both drawings and written descriptions of what the group observes.
  • Investigate Cup 1 - draw and write what you observe - use multisensory observations
  • Investigate Cup 2 - observe as above
  • Investigate Cup 3 - observe as above

9. Observations

  • Did the mixture of substances result in solutions when they were mixed with water?
  • Set Cup 1 in evaporating tray for later
  • Rinse and replace cups and stir sticks in bins.
  • Clean up

10. Results

  • What do you think caused the fizzing in cups 1 and 3?
  • Fizzing in a liquid is caused by gas escaping and coming to the surface.
  • When calcium chloride and baking soda are mixed with water, the gasCarbon Dioxideforms.
  • When citric acid and baking soda are mixed,Carbon Dioxideforms.
  • Carbon Dioxideis the same gas that make the bubbles in soda water.

11.

  • What do you think the white stuff is in Cup 1?
  • The white material is a new substance that formed when calcium chloride and baking soda mixed with water.
  • The new substance,Calcium Carbonate(chalk), is not soluble in water.
  • Settles to the bottom of the cup.
  • When a solid substance forms and settles out of a liquid, it is called aPrecipitate .

12. Changes

  • Production of gas and formation of precipitate are both Changes.
  • When two or more substances are mixed together and a change occurs:
    • Change is Evidence that a Chemical Reaction has taken place
    • Reaction results in new substances with properties that are different from the properties of the original substances
    • Starting substances calledReactants .
    • New substances that form calledProducts .

13. Reactions

  • Did a chemical reaction take place in cup 1?
    • How do you know?
  • Cup 2?
    • How do you know?
  • Cup 3?
    • How do you know?
  • What were thereactantsin cup 1?
  • What were theproductsin cup 1?

14. Carbon Dioxide

  • Carbon dioxide is matter.
    • Made of particles
    • What do carbon dioxide gas particles look like?

15. Matter

  • Everything in the world is made of atoms.
  • Small particles of matter
  • 90 different kinds of naturally occurring atoms on Earth
  • Circles represent atoms
    • C = Carbon
    • O = Oxygen

16. Atoms and Molecules

  • Carbon is a substance
    • Made of Carbon atoms only
    • Carbon atom is the basic particle of the substance carbon
  • Oxygen is a different substance
    • Made of oxygen atoms only
    • Oxygen atom is the basic particle of the substance oxygen

17. Molecules

  • Atoms can combine with one another.
  • When two or more atoms combine, they formMolecules .
  • Basic particle of carbon dioxide is a molecule made of one carbon atom and two oxygen atoms.
  • Homework: Read When Substances Change (pg 28-31) and answer questions
  • Vocabulary next:

18. Vocabulary

  • Carbon dioxide (CO 2 )
    • one of the gases in air.Carbon dioxide can be a product of a chemical reaction.

19.

  • Chemical reaction
    • takes place when two or more substances are mixed together and a change occurs.

20.

  • Change
  • - the process of becoming something different.

21.

  • Energy
    • can take a number of forms and can change from one form to another.
    • Heat is one form of energy and can be released during chemical reactions and when substances dissolve.

22.

  • Evidence
    • used by scientists to support their ideas and conclusions.
    • Evidence is based on observation.

23.

  • Reactants
    • the starting substances in a chemical reaction.
  • Products
    • the new substances that form in a chemical reaction.
  • 6CO 2+ 6H 2 O C 6 H 12 O 6+ 6O 2
  • Reactants Products

24.

  • Precipitate - a solid material that forms as a product of a reaction.

25.

  • Atoms - the smallest particles of matter.Everything is made of atoms.
  • Molecules - atoms combined together.The basic particles of substances.

26. Content

  • What happens when a solution is made with water and two different solutes?
  • Sometimes when two (or more) substances are mixed, a reaction occurs; reactants form new products.
  • How do you know when a chemical reaction has occurred?
  • Changes, such as heat, gas formation, and precipitate formations, are evidence of a chemical reaction.

27. Content

  • What are the basic particles of matter?
  • Atoms are the smallest particles of matter.Atoms can combine to make molecules, which are the basic particles of most substances.
  • Your questions?