Chemical+and+Physical+Changes+Notes

· The 3 main states of matter o Solid o Liquid o Gas

· Matter is anything that has mass and takes up space. · A change is state is a physical change. · The molecules in a solid vibrate when they move. · Heat fusion is the heat required to change a solid into a liquid. · The melting point of water is 0 degrees Celsius or 32 Fahrenheit. · Heat vaporization is the heat required to change a liquid to a gas. · The molecules of a gas bounce around randomly. · Water changing into ice is an example of a physical change. · When a nail rusts it is a form of chemical change. · Another example of chemical change is when food is broken down by enzymes in your stomach. · Another example of physical change is when you break your food into small pieces with your teeth. · Weathering is a form a physical change. Example is a crack in the ground and water gets in it and freezes and causes it to get bigger.

There are many different examples of a chemical change. Chemical change can occur through color, gas formation, solid formation, and temperature change.

Evidence of color change

 * Change in appearance of the Statue of Liberty (in New York), and the Vulcan Statue (in Birmingham).
 * The formation of rust on the USS Alabama (ship in Mobile)
 * Changes when baking a cake (when the mixture changes color)
 * When fruits and vegetables ripen (like green tomatoes turning red)
 * Cleaning a penny with vinegar and salt

Evidence of temperature change

 * Mixing baking soda and vinegar
 * Mixing concrete
 * Composting materials

Evidence of change through the formation of gas

 * Mixing baking soda and vinegar
 * Burning wood
 * Baking a cake
 * Placing effervescent tablets in water (alka seltzer tablets, when you drop them in the water they start to bubble)