Download
slide1 n.
Skip this Video
Loading SlideShow in 5 Seconds..
element PowerPoint Presentation

element

149 Vues Download Presentation
Télécharger la présentation

element

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. element compound Heterogeneous mixture compound

  2. Chemical and Physical Changes

  3. Physical Properties • Physical properties are used to identify, describe and classify matter. • Characteristic of a substance that can be observed (using your senses) without changing the substance into something else.

  4. Chemical Properties • Chemical properties are characteristics involved when a substance interacts with another substance to change its chemical make-up.

  5. Physical vs. Chemical Change • Physical change will change the visible appearance, without changing the composition of the material. • Boil, melt, cut, bend, split, crack • Is boiled water still water? • Chemical change - a change where a new form of matter is formed. • Rust, burn, decompose, ferment Yes, just water molecules in the gas phase

  6. Physical changes do not result in a change of composition. • When a substance changes its composition, it undergoes a chemical change: • When pure hydrogen and pure oxygen react completely, they form pure water. In the flask containing water, there is no oxygen or hydrogen left over.

  7. Chemical Change A change in which one or more substances are converted into different substances. Heat, light and Gases produced are evidence of a chemical change.

  8. Compounds can only be broken down into simpler compounds or elements by chemical changes. The electrolysis of water splits the H2O molecules into H2 and O2 gas.

  9. Does this represent a chemical or physical change? Chemical