8th Chemical and Physical Properties FCAT 8th Chemical and Physical Properties

Engage: Record your response to the probe.

Engage: Record your response to the probe. There was a chemical change when the paper was burned inside the jar. There was light, smoke, ash, and the original paper and it could not be put back together again. (could not be reversed)

Rust is forming on the steel wool No evidence of rust on steel wool Observations of Steel Wool in Vinegar, Water and Air Beaker 1 Steel Wool and Vinegar Beaker 2 Steel Wool and Water Beaker 3 Steel Wool and Air   Rust is forming on the steel wool No evidence of rust on steel wool

Identify the following from the investigations: Test variable – Steel wool Outcome variable- rust Control group- air Experimental group – what liquid the steel wool was in 2. What variables should be controlled in this investigation? The liquids A chemical change occurred in beaker 1 as evidenced by the formation of rust ??? How about baking soda and vinegar forming bubbles and gas You could tear it up into a long skinny section, compress it into a smaller shape. Can you think of others?

All matter has both physical properties and chemical properties All matter has both physical properties and chemical properties. Physical properties are those that can be observed without changing the make-up or identity of the matter. For example, clay is malleable, which means it will bend or flatten when squeezed. Squeezing changes the shape of the clay but does not change what they clay is made of.

Other examples of physical properties include; density-the amount of matter in a given volume, boiling point-the temperature at which a substance changes from liquid to gas, melting-point-the temperature at which a substances changes from a solid to a liquid, electrical conductivity-how well electricity flows through a substance, thermal conductivity-how well heat flows through a substance, solubility-the ability to dissolve in another substance, and magnetic properties.

Chemical properties describe matter based on its ability to change into a new kind of matter with different properties and include; flammability-the ability to burn, reactivity with acids, and tendency to oxidize-form rust.

Based on these properties, matter can undergo two types of changes. Physical changes will result in a change of physical properties such as size and shape. Physical changes are often reversible. Chemical changes will result in producing new substances and are not reversible.

Some evidence of chemical changes may include a change in temperature or color, production of a gas, or production of a new smell. If temperature increases, a chemical change may occur more rapidly.

A mixture is a combination of two or more substances that have not combined chemically. These substances can be separated by physical means. An example of a mixture is fruit salad.

A solution is a mixture that looks like a single substance, but can still be separated by physical means. Within a solution, one substance is dissolved in another substance.

For example; in salt water, salt is dissolved in water. The salt is known as the solute and the water is the solvent. A solution that cannot hold anymore solute is called saturated.

No matter what type of change occurs the Law of Conservation of Mass tells us that the total amount of mass before the change will be the same as the total amount of mass after the change.

Based on the Law of Conservation of Mass the same amount of matter was in the jar even after the paper burned. Even though there is no paper to mass there must be different gases added to the jar that would equal the mass of the paper plus the remaining ash.