Name: Period: Date: UNIT 1: Introduction to Matter Lesson 4: A Fine Line Between Compounds and Mixtures Do Now: PRE-READING OPEN-NOTES QUIZ! By the end of today, you will have an answer to: How do pure substances differ from mixtures? CATALYST Think! What is the difference between salt and salt water? SALT (Compound) SALT WATER (Mixture) Chemical Formula NaCl (s) NaCl (aq) QUESTION: What differences do you notice in the chemical formula for a compound (salt) versus a mixture (salt water)? Draw a Particle Diagram using the key provided on the board. What is the difference between the two particle diagrams you drew? Salt water (NaCl(aq)) The two pure substances that make up salt water are: 1. 2. How can we physically separate the salt from the water?
HOW DO WE REPRESENT MATTER IN CHEMISTRY? MATTER Has Mass and Takes Up Space PURE SUBSTANCE A substance with a uniform and constant composition. ***Pure Substances cannot be separated through physical means***. MIXTURES ELEMENTS A pure substance composed of only one type of atom. Elements cannot be chemically decomposed. Where are they found? The Periodic Table and Table S! COMPOUNDS A pure substance composed of two or more different elements chemically combined. Compounds can be decomposed through chemical means. HOMOGENEOUS MIXTURE Examples: HETEROGENEOUS MIXTURE Examples: Particle Diagram: Particle Diagram:
HOMOGENEOUS AND HETEROGENOUS ONLY REFER TO MIXTURES! REGENTS TIP! If you see homogeneous compound or heterogeneous compound, eliminate those answer choices immediately! Quick Exercise: Directions: Classify each as an element (E), compound (C), or mixture (M). 1. Gatorade 2. Hydrogen Peroxide(H 2O 2) 3. Copper (Cu) 4. Distilled water 5. NaOH (aq) 6. C 6H 12O 6 Aqueous Solutions: When something is completely dissolved in, it is called a. o o Aqueous solutions describe something dissolved in. AQUEOUS = Example: KNO 3(aq) All aqueous solutions are! EXAMPLE QUESTIONS: 1. How do we represent mixtures in a particle diagram? Circle the correct answer. Explain your answer choice: 2. 300. g of a brown liquid is evaporated and a few grams of brown powder remain. The original liquid was a: a. heterogeneous compound b. heterogeneous mixture c. homogeneous compound d. homogeneous mixture 3. A dilute, aqueous potassium nitrate solution is best classified as a a. homogeneous compound b. homogeneous mixture c. heterogeneous compound d. heterogeneous mixture
Name: Pd: Date: Chemistry WORK 1.4- Mixtures 10 points Summary: 1. Explain how a mixture differs from a pure substance. 2. Explain how homogeneous mixtures differ from heterogeneous mixtures. 3. Why do you think there are infinitely more mixtures than pure substances? Regents Review of All Types of Matter! 1. Which substance can be decomposed by chemical change? (Use Table S) (1) beryllium (2) boron (3) methanol (4) magnesium 6. Which is an example of a compound? (1) ammonia (2) calcium (3) diamond (4) uranium 2. One similarity between all mixtures and compounds is that both (1) Are heterogeneous (2) Are homogeneous (3) Combine in a definite proportion (4) Consist of two or more substances 3. Which substance can be decomposed by a chemical change? (1) Co (2) CO (3) Cr (4) Cu 4. Which pair is classified as chemical substances? (1) mixtures and solutions (2) compounds and solutions (3) elements and mixtures (4) compounds and elements 5. An example of a heterogeneous mixtures is (1) soil (2) sugar (3) carbon monoxide (4) carbon dioxide 7. Which is a characteristic of all mixtures? (1) They are homogeneous. (2) They are heterogeneous. (3) Their composition is a definite ratio. (4) Their composition can be varied. 8. Which sample represents a homogeneous mixture? (1) C 2H 5OH (l) (2) C 2H 5OH (aq) (3) C 2H 5OH (g) (4) C 2H 5OH (s) 9. Which material is a mixture? (1) water (2) air (3) methane (4) magnesium 10. In an equation, which symbol would indicate a mixture? (1) NH 3 (s) (2) NH 3 (l) (3) NH 3 (aq) (4) NH 3 (g)
Fun with Particle Diagrams! 1. Identify each as an element, compound or mixture. 2. Given the diagrams X, Y, and Z below: Which diagram or diagrams represent a mixture of elements A and B? (1) X, only (3) X and Y (2) Z, only (4) X and Z 3. Which particle diagram represents a mixture and a compound? Circle the correct diagram. Base your answers to questions 4-6 on the particle diagrams below. Samples A, B, and C contain various particles of matter. 4. Explain why sample A represents a pure substance: 5. Explain why sample C represents a mixture of an element and a compound: 6. Explain what classification of matter is found in sample B:
Name: Pd: Date: Chemistry WORK 1.4- Mixtures Particle Diagram Review 12 points Direction: Classify the following particle diagrams as an element, compound, or mixture and write your answer on the lines provide below the table. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. WRITE YOUR ANSWERS HERE: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
Name: Pd: Date: Chemistry HW 1.4- Extra Review 10 points Directions: Answer all questions based on your knowledge of chemistry. 1. Matter that is composed of two or more different elements chemically combined in a fixed proportion is classified as (1) an isotope (2) a mixture (3) a solution (4) a compound 2. When sodium chloride is dissolved in water, the resulting solution is classified as a (1) Heterogenous compound (2) Homogeneous compound (3) Heterogeneous mixture (4) Homogeneous mixture 3. Which substance can be broken down by chemical means? (1) CO (2) Ce (3) Ca (4) Cu 4. 5. Which is a homogeneous mixture? (1) I 2 (s) (2) I 2 (l) (3) HCl (g) (4) HCl (aq) 6. When sugar is dissolved in water, the resulting solution is classified as a (1) homogeneous mixture (2) heterogeneous mixture (3) homogeneous compound (4) heterogeneous compound 7. A compound differs from a mixture in that a compound always has a (1) homogeneous composition (2) maximum of two components (3) minimum of three components (4) heterogeneous composition 8. Which list of formulas represent compounds, only? (1) CO 2, H 2O, NH 3 (2) H 2, N 2, O 2 (3) H 2, Ne, NaCl (4) MgO, NaCl, O 2 9. Which substance can be decomposed by chemical means (1) tungsten (3) krypton (2) antimony (4) methane 10. Bronze contains 90 to 95 percent copper and 5 to 10 percent tin. Because these percentages can vary, bronze is classified as (1) a compound (2) an element (3) a mixture (4) a substance
Name: Pd: Date: Exit Ticket Quiz 1.4- Mixtures 4 points 1. Which is characteristic of all mixtures? (1) They are homogeneous (2) They are heterogeneous (3) Their compositions are in a definite ratio (4) Their compositions may vary 2. How is a homogeneous mixture different from a heterogeneous mixture?two samples of bronze, a uniform material, are analyzed and found to contain different percentages of tin. Based on this information, bronze is likely a (1) homogeneous compound (2) heterogeneous compound (3) homogeneous mixture (4) heterogeneous mixture 3. An aqueous solution of sodium chloride is best classified as a (1) homogeneous compound (2) homogeneous mixture (3) heterogeneous compound (4) heterogeneous mixture Name: Pd: Date: Exit Ticket Quiz 1.4- Mixtures 4 points 1. Which is characteristic of all mixtures? (1) They are homogeneous (2) They are heterogeneous (3) Their compositions are in a definite ratio (4) Their compositions may vary 2. How is a homogeneous mixture different from a heterogeneous mixture?two samples of bronze, a uniform material, are analyzed and found to contain different percentages of tin. Based on this information, bronze is likely a (1) homogeneous compound (2) heterogeneous compound (3) homogeneous mixture (4) heterogeneous mixture 3. An aqueous solution of sodium chloride is best classified as a (1) homogeneous compound (2) homogeneous mixture (3) heterogeneous compound (4) heterogeneous mixture
Name: Pd: Date: PRE-READING QUIZ 1.4- Mixtures 5 points 1. What is a mixture? [1] 2. What are the two types of mixtures? [1] 3. How are homogenous mixtures and heterogeneous mixtures different? [1] 4. List one example of a homogenous mixture and one example of a heterogeneous mixture. [2] Name: Pd: Date: PRE-READING QUIZ 1.4- Mixtures 5 points 1. What is a mixture? [1] 2. What are the two types of mixtures? [1] 3. How are homogenous mixtures and heterogeneous mixtures different? [1] 4. List one example of a homogenous mixture and one example of a heterogeneous mixture. [2]