Describing Matter

1. Describing
Matter

2. Properties of Matter
 Matter is anything that has mass and
takes up space.
 Matter can be hard, soft, rough or
smooth, round, square, hot or cold.
 It can be small enough to fit in your
pocket or as large as the Earth.

3. States of Matter
 There are three states of matter:
1. Solid (Ice)
2. Liquid (Water)
3. Gas (Water Vapor)
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4. Characteristic Properties
 Some properties of matter, such as size or
amount, are true only for a given sample
of matter.
 For example, a piece of ice can be as
small as an ice cube or as large as a
glacier. The substance is still ice.
 Some properties are true for a particular
kind of substance no matter what the
sample size. These properties are called
characteristic properties. (For
example, all diamonds have the same
hardness.
 Since characteristic properties for a given
substance never change, they can be
used to identify unknown matter.

5. Boiling Point
 The temperature at which a liquid boils is
called its boiling point.
 Boiling point is an example of a
characteristic property of a substance.
 Boiling points can be an excellent way to
tell one liquid from another.
 https://www.youtube.com/watch?v=nVr9
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6. Melting Point
 The temperature at which a solid melts is
called its melting point.
 Because a solid substance melts at one
temperature only, melting point is another
characteristic property.

7. Checkpoint
 What are two examples of characteristic
properties?
1. Boiling Point
2. Melting Point

8. Changes in Matter
 Changes in the state of matter, such as
boiling or melting are examples of
physical changes.
 There are two types of changes in matter:
1. Physical changes
2. Chemical changes

9. Physical Changes
 Physical changes change the form of a
substance, but does not change what the
substance is. (The pop can is still a pop
can, just crushed and the ice is water
even when its solid.

10. Chemical Changes
 In chemical changes, one or more
substances combine or break apart to
form new substances. (Heating sugar and
turning into caramel)
 When the process is complete, the
original sugar particle no longer exists

11.  The ability of a substance to undergo a
specific chemical change is another
example of a characteristic property.
 This property is called the chemical
activity of the substance.

12. Types of Matter
 Matter can be classified into two general
categories:
1. Mixtures
2. Pure Substances (elements and
compounds)

13. Mixtures
 A mixture consists of two or more
substances that are mixed together but
not chemically combined.
 In a mixture the individual substances
keep their separate properties.

14.  Scientists often classify mixtures by how
well they are mixed together.
 In mixtures like ocean water (salt water)
the parts have been blended so well
together that they appear to be a single
substance.
 This type of mixture is called a solution.

15. Pure Substances
 A pure substance is made of only one
kind of matter and has definite properties.
 Examples of pure substances are
sugar, salt, iron, aluminum and copper.
 Every piece of a pure substance is always
the same no matter what the form.

16. Elements
 Some pure substances called elements
cannot be broken down into other
substances by any chemical means.
 Individually or in combination, the
elements form every object in the world!

17. Compounds
 Elements combine in different ways to
form a huge variety of compounds.
 A compound is a pure substance formed
from chemical combinations of two or
more different elements.
 An example of a compound is water .
 Just as symbols are used to represent
elements, formulas are used to represent
compounds.

18. Compound Formulas

19.  The properties of compounds are always
different from the properties of the
elements that formed them.

20. REVIEW
 Using the information you just
gathered, answer the following questions:
1. List the three principal states of matter
and give two examples of each
2. What is the difference between a
physical change and a chemical
change?
3. What is meant by a characteristic
property of a substance?