science

1. Differentiating
Physical and
Chemical Change

2. Substances undergo changes when their conditions
are changed. A change in condition could be a
decreased or an increased in temperature

3. Matter is characterized by their physical and
chemical properties.
Physical properties pertain to those that are
measured without changing the composition of the
substance. These include the color,odor,
texture,boiling point, density,etc.

4. Chemical properties, on the other hands, can be
observed if a chemical reaction has occurred and
thus there is a change in the composition of the
substance.

5. There are two types of changes, physical and
chemical change
When a substance undergoes a change without
affecting the chemical composition of matter then it
is considered a physical change, grinding,
breaking, crushing, bending and changes in the
state of matter are examples of physical changes or
reversible change.
Given examples, melting of ice, dissolving of table
salt, cutting of papers, melting chocolate, bending
(ducting) of metals, and water cycle.

6. Chemical change or irreversible processs involves a
change in the substance’s chemical composition,
that is, new substances are produced. This means
that the new sustance can’t be returned back to its
original case. Given example melting of sugar,
rotting of fruits, burning of sulfur, photosynthesis
process, food digestions and fermentation.

7. Physical change does not lead to a change in the
identity of the substance. Many physical changes
are reversible, especially those involved in phase
change.
Possible signs a physical change has taken place.
 Change of shape
 Change of state (solid, liquid, or gas)
 Change in size
 Change in any other physical property

8. A chemical change involves a change in shape and
its structure of the substance giving a new
substance with new properties.
Possible sign a chemical change occurred.
 A change in color
 A change in the substances’ temperature
 Light is given off.
 A gas is produced.
 A change in taste

9. Figure 1. Composting and Urban Gardening Project
of
Pasig Green Heart Saver