Presentation on theme: "Physical and Chemical Change. Clues of a Chemical Change A new colour appears eg. Oxygen Indicator Solution."— Presentation transcript:
Physical and Chemical Change
Clues of a Chemical Change A new colour appears eg. Oxygen Indicator Solution
Clues of a Chemical Change Heat or light is given off A solid material (called a precipitate) forms in liquid
Clues of a Chemical Change The change is difficult to reverse Bubbles of gas are formed
Situation A piece of dry ice (solid carbon dioxide) is dropped into hot water. Large amounts of white vapour bubble out of the water. Physical Chemical Explanation The bubbles are carbon dioxide gas. There was no chemical change. Just a change in state.
Situation Physical Chemical When George’s father makes wine from crabapples, bubbles form on the surface of the yeast and fruit mixture. Explanation A chemical change from apple juice to wine, it is no longer the same compound.
Situation When margarine is left in a warm place for an extended period of time, it tastes sour. Physical Chemical Explanation The margarine is rotting, which is why it tastes sour.
Situation Jane’s father opens up a new deodorant product. The room quickly smells like fresh flowers. Physical Chemical Explanation The deodorant is still deodorant, some particles have changed to vapour which we smell.
Situation During a school volleyball game, Jennifer sprains her ankle. Her coach squeezes a bag at room temperature that quickly becomes very cold. Physical Chemical Explanation Inside the bag a chemical change has occurred which is endothermic.