INVESTIGATION 4 CHEMICAL REACTIONS WHAT HAPPENS WHEN A SOLUTION IS MADE WITH WATER AND TWO DIFFERENT SOLUTES? HOW DO YOU KNOW WHEN A CHEMICAL REACTIONS HAS OCCURRED?
INVESTIGATION 4PART 1 WHEN A CHANGE RESULTS FROM MIXING TWO OR MORE MATERIALS, THAT CHANGE IS A CHEMICAL REACTION. A REACTION RESULTS IN NEW MATERIALS. FORMATION OF A GAS OCCURS IN SOME REACTIONS. FORMATION OF A PRECIPATE OCCURS IN SOME CHEMICAL REACTIONS.
INVESTIGATION 4PART 1 NEW VOCABULARY REACTANTS ARE THE CHEMICALS THAT ACTUALLY ENGAGE IN CHEMICAL TRANSFORMATION CHEMICAL REACTION IS THE PHENOMENON OR PROCESS THAT CHANGES THE RELATIONSHIPS OF THE ATOMS IN THE REACTANTS PRODUCT ARE THE NEW CHEMICALS THAT EMERGE FROM THE PROCESS.
INVESTIGATION 4PART 1 –CHEMICAL REACTIONS THE BIGGEST IDEA IS THE MATERIAL TRANSFORMATION UNEXPECTED HAPPENING-an explosion, a change in color, or a fizz. The materials that go in don’t come out. What happens to them? Chemicals dissolve in water, meet up with other materials dissolved in water, and form new materials.
INVESTIGATION 4PART 1 –CHEMICAL REACTIONS Gas is tangible in the form of bubbles, but when it breaks free of the liquid and disperses into the air, it is hard to retrieve, both literally and conceptually. So how are we going to keep hold of it? Someone must have a done a good number of investigations during the development of the automotive air bag. Now that’s chemistry in action!!
Our Science Investigation Study Mixtures and solutions Saturation Concentration Reaction
Part 1: Chemical Reactions Chemicals we will use include: Calcium Chloride Baking soda Citric Acid What do you know about them?
Part 1: Chemical Reactions What do you know about solutions? How do you know if a mixture is a solution? What does solubility refer to?
Part 1: Chemical Reactions Do you think these three chemicals will make solutions with water? How can we find out?
Part 1: Chemical Reactions Teams 1,2, 3 will work ONLY with chemical 1 Teams 4,5,6 will work ONLY with chemical 2. Getter 2s, put One spoon of chemical in a cup. Getter 1s, get the water-measuring tools and a craft stick. Add 50 ml of water to your chemical and stir.
Part 1: Chemical Reactions Baking soda is not as soluble in water as calcium chloride, citric acid, or salt. How can we get it to dissolve? WATER As you can see, baking soda and water make a solution and that calcium chloride and water make a solution. What did you observe with the calcium chloride? This is a property of it.
Part 1: Chemical Reactions WE know that citric acid, calcium chloride, and baking soda all from solutions when they are mixed with water. Do you think mixtures of these materials will form solutions when they are mixed with water? For example, if you mix baking soda and calcium chloride with water, will a solution form?
Part 1: FIZZ-Quiz Mat Cup 1: calcium chloride and baking soda. Cup 2: calcium chloride and citric acid. Cup 3: baking soda and citric acid. Investigate
Part 1: FIZZ-Quiz Mat Did the mixtures of chemicals form solutions when they were mixed with water? What do you think caused the fizzing in cups 1 and 2? Fizzing is a production of gas.
Part 1: FIZZ-Quiz Mat Fizzing is a production of gas. 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 gas carbon dioxide(CO2) is formed. Carbon dioxide is the same gas that makes the bubbles in soda.
Part 1: FIZZ-Quiz Mat What do you think the white stuff is in cup 1? The white material is a new chemical that formed when calcium chloride and baking soda mixed with water. The new material, called calcium carbonate, or chalk, is not soluble in water, so it settles to the bottom of the cup. When a new chemical forms and settles out of a liquid it is called a precipitate.
Part 1: FIZZ-Quiz Mat Reaction The product of gas and the formation of precipitate are both changes. When two or more materials (chemicals) are mixed together and a change occurs the change is evidence that a chemical reaction has taken place. A reaction forms new materials with properties that are different from the properties of the original chemicals.
Part 1: FIZZ-Quiz Mat Evidence of a Reaction Did a chemical reaction take place in cup 1? How do you know? Did a chemical reaction take place in cup 2? How do you know? Did a chemical reaction take place in cup 3? How do you know? What new materials formed? Carbon-dioxide gas, calcium carbonate, (chalk). Keep Cup 1 it will be used in part 2.
What a reaction! What is chemical change? What are two examples of chemical reactions at different speeds? What can affect the speed of chemical reactions?
INVESTIGATION 4 CHEMICAL REACTIONS WHAT HAPPENS WHEN A SOLUTION IS MADE WITH WATER AND TWO DIFFERENT SOLUTES? Sometimes when two or more chemicals are mixed, changes take place and new materials form. HOW DO YOU KNOW WHEN A CHEMICAL REACTIONS HAS OCCURRED? Changes, such as heat, gas formation, and precipitate formation, are evidence of a chemical reaction.
Investigation 4 Part 2 Reaction Products WE will need Cup 1 1 funnel 1 filter paper 1 cup Evaporating dishes
Investigation 4 Part 2 Filter the mixture in cup 1 Chalk- which is the precipitate formed from the reaction of calcium chloride and baking soda Chalk reacts to vinegar
Investigation 4 Part 2 Do you think the liquid that came through the filter is a solution? How could we find out? Evaporation Dishes Which chemicals reacted to form a gas? Calcium chloride and baking soda; citric acid and baking soda Which chemicals reacted to form a precipitate? Calcium chloride and baking soda
Investigation 4 Part 2 Breakpoint Observe the results of evaporation Do you recognize the crystals? Have you seen similar crystals before? Where did the salt come from? How did salt get into the cups?
Investigation 4 Part 2 Breakpoint Observe the results of evaporation How can you find out if the liquid that came through the filter is a solution?