Physical and Chemical Properties & Changes Answer Key (CHEM 1405)

Back to Chemistry 1405 Practice Problems

Read each statement and decide if it describes a physical property (PP), physical change (PC), chemical property (CP), or chemical change (CC).

 

____PP___1.  Copper compounds are often blue or green in color.

 

____CP___2.  Copper objects often turn blue or green when exposed to air.

 

____CP___3.  Oxygen gas supports the combustion of fuel.

 

____PP___4.  Metals, when pure, have a high luster (are shiny and bright).

 

____CP___5.  Some metals may become dull when exposed to air.

 

____CP___6.  Milk turns sour if left too long at room temperature.

 

____PP___7.  Mercury’s high density and liquid state at room temperature make it useful in thermometers.

 

____PP___8.  Metals are typically ductile and can be drawn into thin wires.

 

____PP___9.  The hardness of diamonds enables them to be used on drill bits.

 

____CP___10.  Bread dough increases in volume if it is allowed to “rise” before baking.

 

____PP___11.  Tungsten’s high melting point makes it useful for light bulb filaments.

 

____PP___12.  Metals are typically good conductors of heat and electricity.

 

____CC___13.  Two liquids are poured together and a solid substance is formed.

 

____CP___14.  When water is added to cold medicine, bubbles begin to form.

 

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Write three statements describing chemical changes and three statements describing physical changes.  The statements above can give you ideas, but don’t copy the statement.  Each change must be different.  (i.e. Do not cook everything)

 

Chemical  (Answers may vary)

1.  A log burns in the fireplace.

 

2.  Dead leaves decay in the yard.

 

3.  An electric current is run into water, splitting it into hydrogen and oxygen gas.

 

Physical  (Answers may vary)

1.  A glass shatters into many pieces.

 

2.  Soda goes flat at room temperature.

 

3.  Salt dissolves in water.