Introduction to Matter

Think…Think…Think

• What is “stuff” made of?

• What are the smallest bits of things?

• If more than one kind of part makes up a thing, what are those parts?

Ancient cultures

(Alchemists)

Four Elements -water -earth -air -fire

Ancient cultures

- wet when you cut it so it must have water- grows from the ground so it has earth-makes smoke when it is burned so it must have air-can burn so it must contain fire

• Think like an ancient person.

• Potato

• Think like an ancient person.

• Silver

• Think like an ancient person.

• Feather

Limitations to the four elements.

• Developed better systems to help classify matter.

• Matter: anything that has mass and takes up space– Mass – the amount of matter in something– Volume – the amount of space something

occupies

• Which of the following is matter?– A car?– A box?– You?– heat?

Reviewing MATTER

States of Matter

• Matter can be in a solid, liquid, gas, plasma or Bose-Einstein condensates (BEC) state.

• www.chem4kids.com/files/matter_states.html

• www.youtube.com/watch?v=gfP4lwdehuA

Let’s Do an Activity!!

•Stand Up!!• Link arms and make a rigid edge. What

state of matter are we exhibiting?

• Now, hold hands with the person beside you but move a little bit around the area. What state of matter are we exhibiting now?

Activity continued

• Finally, walk freely around the room. What state of matter are we exhibiting?

• Quietly make your way back to your seats!!

Examples of Matter

• Car

• Box

• You

• WaterWhat is not matter?-Heat-Energy-Light

What is a property?

• Property: a characteristic of a substance that can be observed

Physical versus Chemical Properties

Unit II - Part 1The study of matter

Physical Property

Physical property: a property that can be observed without changing the identity of the substance.

Examples of physical properties:

• luster

• malleability: the ability to be hammered into a thin sheet

• ductility: the ability to be stretched into a wire

• melting point

• boiling point

• density

• solubility

• specific heat

Special Physical Properties

• Melting point: the temperature at which a substance changes from a solid to a liquid at a given pressure

water = 0oC

• Boiling point: the temperature at which a substance changes from a liquid to a gas at a given pressure

water = 100oC

Special Physical Properties

• Density: the amount of mass per unit of volume (will be discussed in further detail later)

• Solubility: amount of a substance that can be dissolved in a given amount of solvent

• Specific heat: amount of heat required to change a unit mass of a substance by one degree in temperature.

Chemical Properties

• Chemical property: a property that can only be observed by changing the identity of the substance

Examples of chemical properties:

•flammability

•ability to rust

•reactivity with vinegar

Density

• Density is the amount of mass per unit of volume.

• Density can be used to identify a substance.

• The density of water is 1.0g/mL

Density Calculations

• Formula:

D = m/V = g/mL = g/cm3

Density Examples

#1: A cube has a mass of 3.0 g and occupies a volume of 6.0 ml. Would this object float or sink in water?

Mass = 3.0 g Volume = 6.0 mL

D = 3g/6 mL= 0.5 g/mL

– This object would float in water because its density is less than water (1.0 g/mL).

More Density Calculations

#2: A liquid has a mass of 25.0 g and a volume of 10.0 mL. Use the table below to identify the substance.

Substance Density (g/ mL)

Mercury 13.6

Water 1.00

Ethanol 0.81

M=25.0 g V=10.0 mL

D = 25 g/10 mL

D= 2.5 g/mL

The substance is potassium. Potassium 2.5 g/ml