Synthetic Materials

Before Video

• Chemical reactions occur when the atomic bonds that make up molecules are broken and rearranged.

• A physical change occurs when the size, shape, or appearance of a substance changes but its atomic makeup remains the same.

• A mixture is a substance made by combining two or more different materials in such a way that no chemical reaction occurs. A mixture can usually be separated back into its original components.

• Chemical changes result in new material(s) being formed that have different properties than those that were combined to make them.

• For the most part, physical changes are reversible. However, some physical changes are very difficult or impossible to reverse, such as breaking a rock into smaller pieces.

• For the most part, chemical changes are not reversible because the atoms that make up the molecules have been rearranged to form new substances.

After Video

• A synthetic material is one in which the substances are deliberately joined together to produce a material with different characteristics. Some synthetic materials form from mixtures, but most are the result of chemical reactions.

• Natural resources are resources that exist without humans having any role in their formation.

• Plastics are formed from chemicals that are mixed together and chemically react to create carbon-based molecule chains called monomers. A variety of different chemicals can be used to make plastics, but the most common one today is petroleum.

• Yes, we use synthetic materials for many things, including medicines, fabrics, containers, building materials, and fuels.

• Yes, some synthetic materials, such as plastics, take a very long time to decompose. As a result, they can collect and cause pollution. It is important that these materials are recycled.