Physical ChangesPhysical ChangesEQ: How would you prove EQ: How would you prove whether change in matter whether change in matter was a physical change or was a physical change or

a chemical change?a chemical change?

October 4, 2012October 4, 2012

Physical ChangesPhysical Changes

• Changes to the physical properties of Changes to the physical properties of matter in which the identity of the matter in which the identity of the matter stays the samematter stays the same

• Shape and Size Shape and Size – Cutting a cake into piecesCutting a cake into pieces– Pouring a glass of milk Pouring a glass of milk – Folding clothesFolding clothes– Folding papers to fit neatly into your ISN Folding papers to fit neatly into your ISN

• State State – Melting, freezing, boiling Melting, freezing, boiling – (We’ll look more at this in chapter 7.)(We’ll look more at this in chapter 7.)

• Dissolving Dissolving – To separate the mixture of sand and salt To separate the mixture of sand and salt

from yesterday’s mixtures, you would from yesterday’s mixtures, you would first need to add water to dissolve the first need to add water to dissolve the salt. salt.

Conservation of Mass Lab—Conservation of Mass Lab—Adv.Adv.• Given the following supplies, design an Given the following supplies, design an

investigation for testing the Law of investigation for testing the Law of Conservation of Mass: baking soda, Conservation of Mass: baking soda, vinegar, plastic bag, spoon, scale.vinegar, plastic bag, spoon, scale.

• On p. 50 in your INB, (1) describe your On p. 50 in your INB, (1) describe your investigation, (2) show your data investigation, (2) show your data clearly (mini table), (3) graph your clearly (mini table), (3) graph your data, and (4) write a short conclusion.data, and (4) write a short conclusion.

Is the mass of matter conserved during a physical Is the mass of matter conserved during a physical change?change?

• On p. 50 of your INB, On p. 50 of your INB,

– Find the mass of a small amount of sugar. Find the mass of a small amount of sugar. Record this amount.Record this amount.

– Find the mass of a small container of water. Find the mass of a small container of water. Record this amount.Record this amount.

– Add the sugar to the water and swirl/stir until Add the sugar to the water and swirl/stir until the sugar dissolves.the sugar dissolves.

– Find the mass of the solution. Record this Find the mass of the solution. Record this amount.amount.

– Create a graph of your data.Create a graph of your data.– Write your conclusions. Be sure to use the term Write your conclusions. Be sure to use the term

Law of Conservation of Mass and use your data Law of Conservation of Mass and use your data to support your conclusions.to support your conclusions.

Can the weight of an object Can the weight of an object change?change?

• Use a balance to mass 5 washers. Record Use a balance to mass 5 washers. Record (bottom of page 50 in your ISN).(bottom of page 50 in your ISN).

• Hang from spring scale and record weight Hang from spring scale and record weight (in Newtons).(in Newtons).

• Lower into 500-mL beaker containing 300 Lower into 500-mL beaker containing 300 mL of water. Record (in Newtons).mL of water. Record (in Newtons).

• Write your conclusions. Did the weight Write your conclusions. Did the weight change? Why or why not?change? Why or why not?