Properties of Matter Notes

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Matter Notes

I.

Properties of Matter a.

Matter - Anything that has mass and volume b.

Substance – matter that has the same composition and properties throughout. c.

Property – a characteristic that describes the object / substance

II.

Classifying matter a.

Element – Pure substance made up of only one kind of atom

1.

Ex) iron nail, copper penny, gold ring b.

Compound - Pure substance made up of two or more elements chemically bonded

2.

Ex) water, hydrogen peroxide, sugar, salt c.

Mixture - Combinations of two or more substances that do not combine to make a new substance.

3.

Ex) air, blood, fruit salad, salt water

III.

Compounds a.

Cannot be separated by simple means b.

Elements gain new properties when they form a compound c.

Chemical formula – a way of describing the number of atoms that make up one molecule of a compound

4.

Molecule – smallest particle of a substance that still has the properties of that substance

IV.

Mixtures a.

Each substance retains its own physical and chemical properties b.

Does not need to contain the same amount of each substance c.

Separation techniques: mechanically, filtering, sieves, sifters, evaporation, magnets, distillation, centrifuge d.

Two types of mixtures – heterogeneous and homogeneous

1.

Heterogeneous mixtures – heterogeneous means “different throughout.” Heterogeneous mixtures have larger parts that are different from each other. Ex) milk, taco, suspensions

2.

Homogeneous mixtures – homogeneous means “the same throughout.” Homogeneous mixtures have uniform composition, appearance, and properties. Ex) brass, black coffee, solutions e.

Suspension – a mixture in which the components are dispersed but large enough to see and to settle out.

f.

Solutions – a mixture that looks like a single substance and has the same properties throughout. Solutions can be made of different combinations of solids, liquids, and gasses.

1.

solute is the substance that dissolves in a solution

2.

solvent is the substance that dissolves the solute sugar water ~ sugar – solute water - solvent

3.

Water is called the universal solvent.

4.

Substances that dissolve in another substance are soluble in the substance

5.

Substances that do not dissolve in another substance are called insoluble in that substance.

V.

Solubility – measurement that describes how much solute dissolves in a given amount of solvent at a given temperature. a.

Several factors, including time, motion, temperature, and contact area, affect the rate of dissolving. b.

A saturated solution contains all of the solute it can hold under a given condition. c.

An unsaturated solution contains less than the total amount of solute the solution can hold. d.

A supersaturated solution contains more solute than is normal for that temperature.

VI.

States of Matter a.

Solid – matter that has a definite shape and a definite volume; such as a rock. i.

The particles are compact, touching each other and have a vibratory motion. ii.

Solids have less energy than liquids and gases b.

Liquid – matter that conforms to the shape of its container with a definite volume; for example, water. i.

There is a flowing motion among particles as they are sliding or rolling past each other. ii.

Liquids have more energy than solids but less than gases. c.

Gas – matter than conforms to the shape and volume of its container. i.

The particles are free flowing with random motion and are not touching ii.

Gases have more energy than solids and liquids d.

State or Phase Changes:

1.

Melting is a change from solid to liquid, energy is absorbed

2.

Freezing is a change from liquid to solid, energy is released

3.

Boiling is vaporization which occurs below the liquid’s surface as it changes to a gas, energy is absorbed

4.

Evaporation is vaporization which occurs at the surface of a liquid as it changes to a gas, energy is absorbed

5.

Condensation is a change from gas to liquid, energy is released.

6.

Sublimation is a change from a solid to gas, energy is absorbed

7.

Deposition is a change from a gas to a solid, energy

VII.

Properties a.

Quantitative observation - characteristics which can be measured

1.

Volume

2.

Length

3.

Temperature

4.

Density c.

Extensive properties - directly proportional to the system size or amount of material

1.

Mass

2.

Weight

3.

Volume b.

Qualitative observation - characteristics which are observed with our 5 senses

1.

Smell

2.

Taste

3.

Color

4.

Texture

4.

Height

5.

Depth

d.

Intensive properties - does not depend on the system size or amount of material

1.

States of matter

2.

State changes

3.

Temperature

4.

Appearance – looks, color, shape

5.

Odor – smells

6.

Tastes – flavor e.

Physical property i.

characteristic that can be observed without changing the identity of a substance qualitative and quantitative observations, extensive and intensive properties

7.

8.

9.

11.

10.

12.

13.

14.

Sounds

Texture – smooth or rough

Density

Solubility

Magnetism

Malleability

Ductile

Hardness f.

Chemical property i.

characteristic that cannot be observed without altering the substance

1.

Ability to burn or support burning

2.

Tendency to rust or corrode

3.

Reaction to other substances such as acids and bases

4.

Unexpectedly produce a gas or solid

VIII.

Physical and chemical changes a.

Physical change – form or appearance of matter changes, but composition stays the same. i.

Change does not produce a new substance ii.

Shape can change, but substance does not iii.

Dissolving a solid into a liquid is a physical change iv.

State changes due to the amount of kinetic energy absorbed or released by substances

b.

Chemical change results in a change in the substance’s composition i.

Energy may be gained or released during a chemical reaction ii.

Color can change as a chemical reaction occurs iii.

iv.

Substances may change odor as a result of a chemical change

Formation of a gas or the precipitation of a solid can indicate a chemical change.

IX.

Law of conservation of mass – matter can never be created or destroyed as the result of physical or chemical changes

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