UNIT 1– Matter. What is matter anyway? Matter is ANYTHING that has MASS & takes up SPACE (has VOLUME)

UNIT 1–

Matter

What is matter anyway?

Matter is ANYTHING that has MASS & takes up SPACE (has VOLUME)

Four States of Matter

Solids very low KE (kinetic energy) -

particles vibrate but can’t move around

fixed shape fixed volume

Four States of Matter

Liquids low KE - particles can

move over & around each other but are still close together

variable shape fixed volume

Four States of Matter

Gases high KE - particles have

enough energy to separate and move throughout container; so much so that gases are mostly empty space!

variable shape variable volume

Four States of Matter

Plasma Highest KE - particles collide with

enough energy to break into charged particles (+/-)

gas-like, variableshape & volume

stars, fluorescentlight bulbs

Fluids

What is a fluid? a substance that can FLOW & has

particles that are able to move around each other.

 What 2 phases of matter are considered FLUIDS? Liquids & Gases

Properties of Fluids

What is viscosity? The ability of a liquid to flow or the

resistance to flow. (Honey is MORE viscous than water)

What is buoyancy? The upward force a fluid exerts on

an object.

Properties of Fluids

What 3 properties allow an object to be “buoyant”?1. The buoyant force exerted upward on the

object is ______________________ than the force downward of the object’s weight.

2. The ___________________ of the object is less than the _____________________ of the fluid.

3. The weight of the water displaced by the object is _________________ than the _____________ of the object.

Type of Matter

Kinetic energy

Shape Volume

Solid

Liquid

Gas

Plasma

States of Matter…Test YOUR knowledge!

Type of Matter

Kinetic energy

Shape Volume

Solid Very low Definite/fixed Definite/fixed

Liquid Low Indefinite/not fixed/variable

Definite/fixed

Gas High Indefinite/Not fixed/variable

Indefinite/Not fixed/variable

Plasma Very high Indefinite/ Not fixed/variable

Indefinite/ Not fixed/variable

States of Matter…Test YOUR knowledge!

C. Johannesson

Matter Flowchart

MATTER

Can it be physically separated?

Homogeneous Mixture

(solution)

Heterogeneous Mixture Compound Element

MIXTURE PURE SUBSTANCE

yes no

Can it be chemically decomposed?

noyesIs the composition uniform?

noyes

Colloids Suspensions

Matter Flowchart

Test yourself…

graphite

pepper

sugar (sucrose)

paint

soda

element

hetero. mixture

compound

hetero. mixture

solution

Properties of & Changes in Matter…

Density

Intensive vs. Extensive

Physical vs. Chemical

DENSITY Density is the measure of the MASS of a

substance to the VOLUME of a substance at a given temperature.

Density is expressed in g/mL or kg/L for liquids and g/cm3 for solids.

Density of a SUBSTANCE will determine if the substance will SINK or FLOAT in another substance. (recall buoyancy)

Accuracy vs. Precision

Accuracy - how close a measurement is to the accepted value

PRECISE = CONSISTENT or REPRODUCIBLE

ACCURATE = CORRECTNESS

• Precision - how close a series of measurements are to each other

Accurate & Precise

Precise, not accurate

Accurate, not Precise

Neither Accurate nor Precise

Example Problem

To determine the density of a certain metal alloy, a chemist

measures the mass and volume of each of four different samples of the alloy. The chemist obtains the density values shown in the

following:

Example Problem

Sample Density (measured)

1 5.87 g/cm3

2 5.89 g/cm3

3 5.83 g/cm3

4 5.92g/cm 3

Example ProblemLater, the chemist learns that the true

density of the alloy is 5.62 g/cm3. Describe the chemist’s results in terms of accuracy and precision.

a. accurate and preciseb. accurate, but not precisec. precise, but not accurate d. neither accurate nor precise

PHYSICAL CHANGES Physical Change

changes the form of a substance without changing its identity

EX: cutting, dissolving, grinding

Changes of state (phase changes)

are physical changes that

involve changes of energy.

PHASE CHANGES

SOLID LIQUID GAS

sublimation

melting vaporization

freezing condensation

deposition

Phase Changes (ARE physical change)

CHEMICAL CHANGES

Chemical Change

changes the identity of a substance

products have different properties

EX: tarnishing, burning, corroding

Physical vs. Chemical Indicators or Signs of a Chemical

Change (*important…you will need to know this for the rest of the year!!!)NEW substance formedChange of color or odorRelease or formation of a gasformation of a precipitate (solid

that settles…yes, a suspension)change in light or heat

Physical vs. Chemical CHANGE

You try it…(not in notes)

rusting iron

dissolving in water

burning a log

melting ice

grinding spices

chemical

physical

chemical

physical

physical

Physical vs. Chemical

Physical Property

can be observed without changing the identity of the substance

Chemical Property

describes the ability of a substance to undergo changes in identity

Physical vs. Chemical PROPERTY

You try it…

melting point

flammable

density

magnetic

tarnishes in air

physical

chemical

physical

physical

chemical

Other properties

Conductivity- the ability of energy to flow through something.

Reactivity- how likely a substance is to react with other substances

Boiling Point- the point when a liquid becomes a gas

Freezing/Melting Point- the point when a liquid becomes a solid

Mine

Scientific Notation

In science, numbers can be very small & very large (confusing!)

Numbers can be expressed in Scientific Notation:

M x 10n 1 ≤ M < 10 +n:

large # -n: small #

Scientific Notation To convert into Sci. Notation:

Move decimal until there’s 1 digit to its left. (# of places moved = exponent)

Large # (>1) positive exponentSmall # (<1) negative exponent

Only include sig figs.

65,000 kg 6.5 × 104 kg

Scientific Notation Practice Problems

1. 2,400,000

mg

2. 0.00256 kg

3. 7 10-5 km

4. 6.2 104 mm

2.4 106 mg

2.56 10-3 kg

0.00007 km

62,000 mm

Calculating with Scientific Notation

(5.44 × 107 g) ÷ (8.1 × 104 mol) =

5.442nd2nd

EEEE÷÷

2nd2nd

EEEE ENTERENTER7 8.1 4

= 671.6049383 = 670 g/mol = 6.7 × 102 g/mol

Type on your calculator: