Matter

Matter makes up everything in our universe

Matter has four physical states

  1. solid3. gas
  2. liquid4. plasma

Matter is made of atoms that bond to make molecules.
When two different kinds of atoms (elements) bond they form a compound

If different types of molecules or atoms are found together, but they are not bonded then they are called a mixture

If something is composed of one type of atom it is called an element.

Examples of Elements:

  • Gold
  • Silver
  • Aluminum
  • Oxygen
  • Carbon
  • Molybdenum

Examples of Compounds:

  • Salt (NaCl, sodium and chlorine bonded together),
  • Water (H2O, 2 hydrogen atoms bonded to one oxygen atom),
  • Sugar (C6H12O6)

Examples of Mixtures:

  • Kool-Aid (Sugar, water, flavoring, coloring)
  • Sea water (water, salt, magnesium, calcium)
  • Air (Oxygen, Nitrogen, and other gasses).

Properties of Matter

Matter is stuff that has massand volume.

Properties are used to describe a substance. Some properties of matter include:

  1. Hardness
  2. Texture
  3. Temperature
  4. Density
  5. Flammability

Characteristic properties of matter are properties that CANNOT change!

Characteristic properties are used to identify unknown substances

These include:

Boiling point: When a liquid turns into a gas

Melting point: When a solid turns into a liquid

Density: The amount of mass in a given space or volume

Substance / Melting Point /

Density

/ Boiling Point
Water / 0 C / 1.0 g/mL / 100 C
Ethanol / -114.3 C / 0.789 g/mL / 78.4 C
Table Salt / 801 C / 2.16 g/mL / 1465 C

States of Matter

SOLIDS:

  • Solids have a definite shape and volume, this is because theatoms or molecules are packed together very closely.
  • The molecules or atoms of a solid move in place.
  • In most cases the solid state of a substance is the mostdense because the molecules or atoms are the closest together in the solid state.
  • Exception: Ice
  • Picture:

LIQUIDS:

  • Unlike solids, liquids have no definite shape
  • A liquid will take the shape of its container
  • Liquids do have a definite volume
  • The atoms or molecules will movearound freely within a given volume.
  • The liquid state is usually the second most dense form of a substance because its atoms or molecules are more spread out then in the solidstate.
  • Picture:

GASES:

  • Unlike liquids and solids, the volume of a gas can change very easily.
  • Gases do not have a definite shape or volume
  • Gases will take the shape and volume of the container they are in
  • Atoms of a gas move around freely and they are in constant motion.
  • Gas atoms bounce off of each other and any other barriers they come in contact with.
  • Picture:

PLASMA:

  • Plasma is partially ionized gas
  • Plasma is rare on earth
  • Plasma is found in the outer planets, stars and sun
Movement of Molecules
Atoms and molecules are constantly moving. As a substance is heated its molecules or atoms will gainenergy and move faster. As a substance is cooled its molecules or atoms will lose energy and move closer together.
ALL MATTER HAS VOLUME

Volume is the amount of space something occupies

Liquid Volume:

Use a graduated cylinder to measure volume.

Remember to read from the bottom of the meniscus.

Units used: mL, cm3, and liters.

Solid Volume:

All objects have volume

Formula: l x w x h = volume

What if a shape is irregular (not square or rectangular)?

Measure how much the water in a graduated cylinder rises.

Gas volume:

Can you measure the volume of a gas??

You can, but it changes easily.

All Matter Has Mass

Mass is the amount of matter something has

Mass can only change if an object's size changes

example:

Units: grams, kilograms, milligrams

So is there a difference between mass and weight?

YES!!!

They are different

Gravity is a force between two objects

I.e.: if you go to the moon does your weight change?

But does your mass???

So what is weight?

Weight is the gravitational force on something

Humans have mass – earth has mass – they are attracted to one another

The Differences between mass and weight

Mass is . . .
A measurement of the amount of matter in an object
Always stays same it never changes
Measured with a balance.
Expressed in g, kg, and mg / Weight is. . .
A measure of gravity’s force on an object
Changes depending on where the object is in relation to the earth
Measured on a weight scale
Expressed in Newtons

All Matter Has Density

Density: The amount of mass in a given space or volume.

Density is found by dividing mass by volume. Density gives us an idea of how close together a substance’s atoms or molecules are. A substance with a high density has particles that are very close together. A substance with a low density has particles that are far apart.

FORMULA: D= M / V

Density’s units are always the units of mass/the units of volume

Units: grams, mL, cm3

Example Problems:

1.Find the density of a substance with a mass of 5 kg and a volume of 43 m3

First – Write the equation

Second: Do the Math – Don’t forget your units

  1. Density = mass/volume
  2. Density = 5kg/43m3
  3. Density = 0.12 kg/m3

2.A block of pinewood has a mass of 120 grams and a volume of 300 cm3. What is the density of the wood?

  1. Density = mass/volume
  2. Density = 120 g./300 cm3
  3. Density = 0.4 g/ cm3

Why is density important?

  1. Every substance’s density remains the same at standard temperature and pressure. Each substance has a characteristic density.
  1. The density of one substance is normally different than another substance.
  1. Density is one way scientists can identify substances.
  1. If a substance is unknown it can be identified by its density.

Describing Matter

Physical Properties: ______characteristics

(Can be observed without changing the identity of the matter)

I.e.:

Physical Properties - Things you need to know

Physical Property / Definition / Example

Thermal Conductivity

State

Malleability
Ductility
Solubility
Density