Study Guide Chemistry Name Period 1. What is matter? Matter is anything that has mass and takes up space. 2. List 3 examples of matter and 3 non-examples of matter. EXAMPLES NN-EXAMPLES 1. _air 1. time 2. _any gas (ex. oxygen) 2. electricity 3. _any solid or liquid 3. heat (ex., desk, water) 3. Look at the examples below. Circle the ones that are examples of a physical change. a. defrosting frozen vegetables in the microwave b. baking cookies c. adding 15mL of salt to 50mL of water d. starting the engine of a car e. making pancakes 4. What is the difference between dissolving sugar in water and making cookies with sugar in them? Dissolving sugar in water is a physical change; it is still sugar and water, the sugar just spaces out between the water molecules. Baking cookies is a chemical change. The cookies are a different substance than the batter. 5. What is an atom? An atom is the smallest unit of matter. It is the smallest unit of an element that still has the properties of that element. 6. For each of the objects, list 5 physical properties you could identify for the following items. a. milk temperature, state of matter, color, volume, mass, density, transparency, viscosity b. paper clip state of matter, volume, mass, density, luster, color, shape, size
7. Complete the chart identifying the characteristics of the different states of matter. Describe the shape and How are the particles moving? volume Gas No definite shape; No definite Fast and away from each other volume Liquid No definite shape; takes the Slide and glide past each other shape of the container. Definite volume Solid Definite shape; definite volume Vibrate in place. 8. What moves in or out of matter as it changes state? Heat energy 9. Label the state of matter: solid gas liquid 10. What are 3 signs that a chemical change has occurred? a. Release of odor not easily reversed b. Change of color fizzing/creation of a new gas c. Release or gain of heat or light energy creation of a new solid 11. When you mix red Play Doh with blue Play Doh you can observe a color change, creating purple Play Doh. Is this a physical or chemical change? Explain. _This is a physical change because it is still just Play Doh. Even though it is a new color, a new substance was not created. 12. Identify each of the following as either a Chemical change (C) or a physical change (P). 1. P making ice cubes 2. C toasting bread 3. P painting a wall 4. C burning a candle 5. P carving a pumpkin 6. P making chocolate milk
13. Label the diagram with the following terms: nucleus, electron, atom, proton, neutron. Identify the charge of the protons, neutrons, and electrons. The Atom Proton (positive charge) Electron (negative charge) Nucleus Neutron (no charge) 14. Identify the elements or their symbols: 1. C Carbon g. Hydrogen H 2. xygen h. Nitrogen N 3. P Phosphorus i. Sulfur S 4. Ca Calcium j. Iron Fe 5. Cl Chlorine k. Potassium K 6. Na Sodium 15. What is the difference between a mixture and a compound? A compound is made of 2 or more elements that are chemically combined and has different properties than the elements that make it up. A mixture is made of two or more substances that don t chemically combine and keep the properties of its components. 16. For number 16, write E if the description is an element, C if it is a compound, or M if it is a mixture. M a. apple juice E b. aluminum M c. a bag of m&ms C d. calcium chloride C e. salt E f. silver C g. water M h. hot cocoa C i. nitrous oxide
For numbers 17-18, draw a model to represent the given chemical formula. Use the symbols that represent each element to identify that element. 17. 18. # of molecules: 1 Element Number Hydrogen 1 Nitrogen 1 xygen 3 # of molecules: 4 Element Number Sodium 1 xygen 1 Hydrogen 1
For numbers 19-20, write a chemical formula to represent the given model. 19. 20.. Ca Cl S S S CaCl 3 3S 2 For number 21, Write Ho if the mixture is homogeneous or He if it is heterogeneous. Ho a. iced tea He b. a bowl full of Halloween candy He c. water and sand Ho d. water and salt He e. salt and pepper Ho f. a solution 22. List and describe 3 ways to separate a mixture. a. _evaporation/ add water and evaporate b. _filter c. _physical separation of larger pieces d. _use a magnet to pull out magnetic substances 23. Define the following: a. Boiling point: the temperature at which a liquid becomes a gas b. Melting point_the temperature at which a solid becomes a liquid c. Freezing point the temperature at which a liquid becomes a solid
24. 28 Ni Nickel 58.693 A. Atomic Number 28 B. Atomic Mass 59 C. # of Protons 28 D. # of Neutrons 31 E. # of Electrons 28 86 Rn Radon 222 F. Atomic Number 86 G. Atomic Mass 222 H. # of Protons 86 I. # of Neutrons 136 J. # of Electrons 86 73 Ta Tantalum 180.948 K. Atomic Number 73 L. Atomic Mass 181 M. # of Protons 73 N. # of Neutrons 108. # of Electrons 73 25. Jenna wants to know if drinking Slim Fast will help her lose weight. She has a group of ten people replace their breakfast and lunch with Slim Fast shakes and bars for 1 month. She has another group of ten people eat as they normally would. She weighs all 20 people at the beginning and end of the month and compares their weight. a. What is the independent variable? Slim Fast b. What is the dependent variable? weight c. What is the control group? the group that eats as normal d. Write a hypothesis: _If Slim Fast is consumed, then weight will decrease.
What is one example from the passage of chemical changes in nature? The passage lists the process of breathing and lighting a fire with wood as examples of chemical changes in nature. Explain why the author says that chemistry is a pretty powerful thing. Chemistry can produce powerful things like bombs or life-saving drugs. It is powerful because it makes up the whole universe.