next. physical change “the physical properties of a substance change, but the identity of the...

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Chemical Properties A chemical property is any characteristic that gives a substance the ability to undergo a change that results in a new substance. 4 Examples of chemical properties: –Reacts to water –Reacts to light –Reacts to oxygen –Flammability

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NEXT Physical Change The physical properties of a substance change, but the identity of the substance does not change. NEXT Chemical Properties A chemical property is any characteristic that gives a substance the ability to undergo a change that results in a new substance. 4 Examples of chemical properties: Reacts to water Reacts to light Reacts to oxygen Flammability Chemical Change A change in the identity of a substance due to the chemical properties of that substance. A NEW substance or substances are formed as a result of the change. NEXT Signs of a Chemical Change Bubbles Production of Heat Light Smoke Change in Color Sound NEXT Is a chemical change reversible? A chemical change can only be reversed by a chemical reaction, not by physical means. Are these examples chemical or physical changes? NEXT A Rusting Bicycle ANSWER Chemical Change Oxygen in the air reacts with the metal of the bicycle. This produces a new substance called rust. NEXT Melting Butter for Popcorn ANSWER Physical Change Heating causes the butter to change from a solid to a liquid. The identity of the butter does not change. NEXT Hammering Wood Together to Build a Birdhouse ANSWER Physical Change Hammering the wood together causes the wood to change shape. The identity of the wood does not change. NEXT Spoiling Food ANSWER Chemical Change Spoiling food changes color and has a foul odor. Bacteria, mold, enzyme action, and oxidation cause spoilage. NEXT Mixing Lemonade Powder into Water ANSWER Physical Change After mixing the lemonade powder and water, lemonade powder and water are still present. Evaporating the water separates the ingredients. NEXT Mowing the Lawn ANSWER Physical Change Cutting the grass does not change the identity of the grass. NEXT Fireworks Exploding ANSWER Chemical Change Fireworks are composed of different metals, such as copper. After ignited, the fireworks produce light, heat, and sound. NEXT Water Boiling ANSWER Physical Change When water boils, water changes from a liquid to a gas. The identity of the water does not change. NEXT Photosynthesis ANSWER Chemical Change Plants change carbon dioxide, water, and sunlight into sugar and oxygen. New substances are formed. NEXT Separating a Mixture of Rocks and Sand ANSWER Physical Change Separating the rocks from the sand can be done by physical means. The identities of the rocks and sand do not change. NEXT Adding Food Coloring to Water ANSWER Physical Change The identities of the substances did not change. Water and food coloring are still present. NEXT Adding Vinegar to Baking Soda ANSWER Chemical Change Gas bubbles were produced. The baking soda and vinegar reacted to form bubbles of carbon dioxide. HOME Can HEAT cause a chemical reaction? YES ! Can LIGHT cause a chemical reaction ? YES, Photosynthesis What is a sign of a physical change? A change in a physical property : Shape, size, length, change phase (solid, liquid, gas) SIGNS OF A CHEMICAL CHANGE: HEATLIGHT SMOKEBUBBLES COLOR CHANGE SOUND NEW IDENTITY CANT BE REVERSED BY PHYSICAL MEANS What is.? A change in the identity of a substance due to the chemical properties of that substance. Chemical change What is.? Any characteristic of a material that can be observed or measured without changing the identity of the material. Physical property Any characteristic that gives a substance the ability to undergo a change that results in a new substance. Chemical Property What is.? Any characteristic of a material that can be observed without changing the identity of the material. Physical Property Examples of Physical Properties : Boiling pointfreezing point Melting point Volumeshape Densitylength ColorMass Examples of Chemical Properties: Flammability Reacts with oxygen Reacts with H20 Ability to change with light A ___________change results in a new substance, with a new. IDENTITY