Properties of Matter Objective 4 – Changes in Matter

1. Properties of Matter Objective 4 – Changes in Matter

2. A puddle of water evaporating Rust flaking off a metal fence What do these have in common? Both are evidence that matter constantly changes in form as it under goes physical and chemicalchanges. However, during such changes, no matter is created or destroyed. Thus, the total amount of matter (mass) remains constant. “The Law of Conservation of Mass”

3. Which statement supports the law of conservation of mass? • The total mass of the reactants is greater than the total mass of the products. • The total mass of the reactants is less than the total mass of the products. • The total mass of the reactants equals the total mass of the products. • Mass can be created and destroyed. HINT!! Now, you have to think through the words… turn the sentence into a picture / symbol / diagram / equation…

4. Which statement supports the law of conservation of mass? • The total mass of the reactants is greater than the total mass of the products. • B. The total mass of the reactants is less than the total mass of the products. • C. The total mass of the reactants equals the total mass of the products • D. Mass can be created and destroyed. mass of reactants > mass of products mass of reactants < mass of products mass of reactants = mass of products which we know is WRONG, WRONG,WRONG 

5. Parts of a Chemical Reaction Products What you’ve got What you get Reactants

6. Parts of a Chemical Reaction Products What you’ve got What you get Example: Ingredients: Milk, Flour, Egg, Chocolate Product: Cookie Reactants

7. Parts of a Chemical Reaction Products What you’ve got What you get Example: Ingredients: Milk, Flour, Egg, Chocolate Product: Cookie The Law of Conservation of Mass: The mass of the products is equal to the mass of the reactants. In other words, matter cannot be created or destroyed. If the ingredients have a mass of 16 grams, then the reactants have a mass of ________. 16 g Reactants

8. The Law of Conservation of Mass Reactants Products A + B AB 5 g + 6 g 11 g • The total mass of the products have the same total mass as the reactants – ALWAYS. • The arrow always points to the product(s) of the chemical reaction

10. heat CaCO3 CaO + CO2 The chemical equation shows CaCO3 being heated. Which of these statements best describes the mass of the products if 100 g of CaCO3 is heated? A. The difference in the products’ masses is equal to the mass of the CaCO3. B. The sum of the products’ masses is less than the mass of the CaCO3. C. The mass of each product is equal the mass of the CaCO3. D. The sum of the products’ masses equals the mass of the CaCO3. REMEMBER!! Now, you have to think through the words… turn the sentence into a picture / symbol / diagram / equation…

11. heat CaCO3 CaO + CO2 • The chemical equation shows CaCO3 being heated. Which of these statements best describes the mass of the products if 100 g of CaCO3 is heated? • A. The difference in the products’ masses is equal to the mass of the CaCO3. • B. The sum of the products’ masses is less than the mass of the CaCO3. • C. The mass of each product is equal the mass of the CaCO3. • D. The sum of the products’ masses equals the mass of the CaCO3. CaCO3 = CaO – CO2 CaCO3 > CaO + CO2 CaCO3 = CaO = CO2 CaCO3 = CaO + CO2

13. Spend 2 minutes reading through the 2 Example problems. Any questions?

14. Calculators out! You will now work on 5 Conservation of Mass problems on your own. Show your work. Remember, reactants and products must be EQUAL! You have 10 minutes to work.

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26. Check your answers Find a friend (without moving from your seat) and check your answers against their answers. If they differ, figure out why. You have 2 minutes.

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30. Check your answers! 1. 40g magnesium oxide 2. 5g solid yellow precipitate 3. 23g sodium 4. 66g oxygen 5. 4.0g magnesium oxide

31. FIZIX for sofomores TAKS review 2011 Let’s hear it for the Class of 2013!!!

32. PHYSICS Fact #1: You haven’t even had Physics and it’s on TAKS. Not fair. Fact #2: In this packet you are going to learn some tricks to get around Fact #1 so that you will be SUCCESSFUL anyway!

33. The state guy 1 says, “Hey, let’s give those sophomores a real test. Let’s make ‘em do Physics – they won’t even take the class until they are Juniors…” • State guy 2 says, “Great idea. Let’s do it”

34. You think OMG – I can’t do Physics. I haven’t even had the class BUT…….You have been doing FIZIX your WHOLE life (even before you were born) and the really GREAT thing is you have even had physics. In 6th, 7th and 8th grade those sneaky science teachers were busy teaching you physics and you were busy learning FIZIX cause nobody called it “Physics” (too big and bad and hard and scary…yeah right!!) so, you just did it because…

35. FIZIX is PHUN!!! • You are around Physics everyday, still, and without thinking about it you do FIZIX all day everyday. Now, together, we are gonna put the PHYSICS and the FIZIX together so you can show the state… “I GOT THIS…BRING IT ON!!!”

36. These questions are the… • “icing on the cake” • “trick up your sleeve” • “ticket to the top” • So , you are gonna use these questions not to just pass the test but as your own “secret weapon” to be commended!!!!

37. We are gonna “crack the code”! We are goin’ “behind the scenes”! • YOU WILL OWN THIS TEST!!! • Literally everything you need to do all of the calculations is on the formula chart the state has so kindly provided…I bet they didn’t count on us figurin’ that out..ha ha…

38. Teachers: Pass out a formula chart to each student.

39. you do work Work = force x distance W = Fd THAT”S FIZIX!!!

40. you have momentum Momentum = mass x velocity p = mv THAT’S FIZIX!!!

41. you convert Gravitational potential energy = mass x acceleration due to gravity x height PE = mgh THAT’S FIZIX!!!

42. you are efficient % efficiency = work output (wO) x 100 work input (wI) % = wO x 100 wI THAT’S FIZIX!!!

43. see…ain’t no big thang… so, let’s do FIZIX!!!

44. There are FOUR simple steps to problem solving, which you already know but let’s review.

45. Read The FULL Question 1. RTFQ-- (what am I looking for????)

46. Find The Formula 2. FTF-- (find “what you are looking for” on your formula chart)

47. Replace The Variables (variables, as you know from math, are those letters we use to hold the spot in a formula until we know the number and unit to put in) 3. RTV--

48. Do The Math 4. DTM-- (remember you must respect the ORDER OF OPERATION):

49. Parentheses Exponents Multiplication Division Please Excuse My Dear Aunt Sally: Addition Subtraction

50. The picture shows a cube that contains 20 mL of a solution. The solution has a mass of 40 grams. What is the density in g/mL of this solution?