Physical & Chemical PROPERTIES

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1 Name Test Date Hour Group Chem #4 Notebook Properties & Changes LEARNING TARGETS I can give examples of physical and chemical properties. I can give examples of physical and chemical changes. I can identify evidence of chemical change. I can identify the Law of Conservation of Matter in a chemical change. Chemistry #4 - Vocabulary: Bond The connection joining two or more atoms Chemical Change - A change of one substance into a new one with different chemical and physical properties. Chemical Property - Characteristics of a substance that cannot be observed without changing the composition (make up) of the substance. Law of Conservation of Matter - Matter is neither created nor destroyed in a physical or chemical change. Precipitate - Solid that comes out of its solution because of a chemical or a physical change. Physical Property characteristic that can be observed without changing or trying to change the composition of the substance Physical Change change in which the form or appearance of matter changes but not its composition Reaction a process that leads to one set of substances transforming into another substance Evidence facts, data or information indicating whether a belief is valid or true Physical & Chemical PROPERTIES Physical properties are characteristics that can be without trying to change the composition of the substance. All substances have their own set of unique physical properties such as, _, density, color and. Chemical properties are characteristics that be observed without changing the composition of the substance. All substances also have their own set of unique chemical properties. Examples of chemical properties are paper will, metal will _ and food will _. Physical Properties Chemical Properties Summing it up: The difference between a physical and chemical property is that A physical property is something I can observe without the of the substance. AND A chemical property cannot be observed until you the of the substance.

2 Physical & Chemical CHANGES Physical changes occur when the form or appearance of matter changes but not its _. For example ripping is a physical change because you still end up with paper. Melting ice is also a physical change because you still end up with. When the substance you end up with is different than the substance you started with scientists call it a _ change. A chemical change occurs when the composition of a substance changes into a substance with physical and chemical properties. A common example of this type of change is. When an object - say an iron nail- is exposed to water and air it rusts and isn t an iron nail anymore; it turns into iron oxide. These are _ types of matter that have entirely properties than the original iron nail. Rusting is a change. Physical Changes Chemical Changes Matter Can undergo types of changes Physical Change Chemical Change No break and no new form. The substances remain the. Bonds and new bonds. Produces substances with properties. Examples of Physical Changes Examples of Chemical Changes

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4 YTS #1 Chemical Changes Rotate through the following stations. You must wear safety GOGGLES at all times. Materials: 2 small bags, yeast, sugar, salt, warm water, spoons, graduated cylinder 1. Use the marker to label each bag. Salt Water and Sugar Water (and your hour #) 2. Put a small teaspoon of yeast in each bag. 3. Add 25 ml of salt water to the first bag, rinse the graduated cylinder. 4. Add 25 ml of sugar water to the second bag, rinse the graduated cylinder. 5. Try to get as much air out of the bag as possible and seal each bag. 6. Leave the bags at your station overnight while we give this time to react. Salt Water Sugar Water Materials: 2 pennies, forceps, vinegar and salt solution, water 1. Using the forceps dip 2 pennies (one at a time) into the vinegar and salt solution for about 20 seconds. 2. Directly from the solution place one penny in the not rinsed area. 3. Using the forceps take the second penny and rinse it off in water for about 20 seconds. 4. Place the second penny in the rinsed area 5. Allow the reaction time to react overnight. Rinsed Penny Not Rinsed Penny

5 Materials: banana slice, clay, paper towel, plastic knives 1. Keeping the peel ON both substances, slice off about an inch of the banana. With a different knife, slice off about an inch of clay. 2. You are going to observe the two substances to see which reacts with oxygen. 3. Unpeel your two substances, exposing them to oxygen, and place them on the paper towel. 4. Observe for 3-5 minutes allowing a reaction (if any) to take place. Banana Clay Materials: milk, water, lemon juice, 2 petri dishes, 2 stirrers, dropper 1. Cover the bottom of one the dish with milk and the other with water. 2. Add 2-3 dropper full of lemon juice to each petri dish and allow the reaction to take place. 3. If you notice there is no change to either, add a few more drops of lemon juice and stir. 4. Observe for 1 minute allowing a reaction (if any) to take place. Milk Water Materials: metal pan, match 1. Carefully, light the match. 2. Hold the match over the metal pan and observe as it burns. Match Materials: baking soda, water, vinegar, cup, spoon, graduated cylinder 1. Measure and pour 25 ml of water into one cup and 25 ml of vinegar into the other cup. 2. Put 1 teaspoon of baking soda into each cup. 3. Observe and allow any possible reaction to occur. Water Vinegar

6 Materials: Ammonium Nitrate, Water, cup, stirrer, thermometer 1. Put about 100 ml of water in your cup. 2. Record the temperature of the water in the beaker. O C 3. Take ONE teaspoon of Ammonium Nitrate and pour it into your cup. 4. Stir the solution with the stick. Ammonium Nitrate Materials: Calcium Chloride, Water, cup, stirrer, thermometer 1. Put about 100 ml of water in your beaker. 2. Record the temperature of the water in the beaker. O C 3. Take ONE teaspoon of Chloride and pour it into your cup. Observe the temperature in 2-4 minutes. Calcium Chloride 1. Watch the following experiment Warning: Do NOT try this at home! Gummy Bear

7 Evidence of Chemical Changes How do you know which type of change (Chemical or Physical) has occurred? Here are 4 common signs of that a change has happened. Examples A banana exposed to oxygen turns green leaves dying and turning & in the fall a silver necklace tarnishing and turning an iron nail rusting and turning a piece of bread toasting and turning (a solid that will settle out of a liquid) Examples When lemon juice is added to milk, forms Soap and water react and produce in your shower Lead nitrate (liquid) and potassium iodide (liquid) react and produce (yellow solid) _ (giving off light energy and/or heat energy) Examples Burning a _ Gummy Bear and Potassium Chlorate produces a reaction Calcium Chloride will the temperature of water Your cells turning glucose and oxygen into _, water and carbon dioxide Fuel burning produces _, carbon dioxide and water vapor solids produce a gas) Examples Baking soda and vinegar produced Yeast and sugar water produced _ Burning wood produces _ and water vapor Cows digesting food produce _ ewwww Alka-seltzer and water produce (mixing liquids and/or

8 YTS #2 Mass Before and After Yesterday, your teacher put 100 ml of hot water into a bag of sugar and yeast. She found the mass of these to be. Overnight the yeast chemically reacted with the sugar water. The mass the next day is. What do you notice? Law of Conservation of Matter Just like in a physical change, in a chemical change the cannot change. The number of that you start with is the as the number of atoms you end up with. This is called the _ of Conservation of which states that matter is neither nor. The mass of the substance a physical or chemical change is to the mass of the substance a physical or chemical change. What you start with is what you end with - in atom terms anyways! You start with the two chemicals: & These have a mass of. You end with the two chemicals: & These have a mass of. In a chemical reaction, the atoms are not in the reaction and no new atoms are. The atoms just. Match each chemical change with the correct evidence that the reaction occurred. Chemical Change Arrows Evidence Baking soda and vinegar react and carbon dioxide bubbles form. Change in color Sodium (Na) and Chlorine (Cl) react so violently that flames can be seen. Precipitate forms When Silver Nitrate (AgNO 3) and Sodium Chloride (NaCl) react they form Sodium Nitrate (NaNO 3) and a solid substance called Silver Chloride (AgCl). Heat is given off When copper carbonate (bluish-green)) is heated copper oxide ( black) is formed. Gas forms According to the Law of Conservation of Mass if there are 12 atoms before the reaction then there will be atoms after the reaction has taken place. Iron and Oxygen react to form iron oxide. If the mass of the iron oxide is 1.2 g and the mass of the iron before the reaction took place was 1 g, what is the mass of the oxygen before the reaction? We have now finished the Chem #4 Notebook. Please flip to the front page and check your Learning Targets.