SNC1

Particle Theory of MatterWhat two experiments that suggested that matter is made of particles:

a) _____________ alcohol and water result in a combined volume that is _________ than the volumes of the original water and alcohol added together. This suggested that different sized particles were combined and the __________ particles were fitting_________ the larger particles.

b) When __________ and nitric acid are reacted together to make a new _______- coloured substance. When this new substance was reacted with Aluminum, the __________ was regenerated. This suggested that the particles of matter are not ____________ when chemical reaction occur.

The Particle Theory1) All matter is made of _____________.2) Particles cannot be ____________ or _____________.3) Particles are in a constant state of _______________.4) The higher the temperature, the _____________ the particles move.5) Particles are _____________ to each other by forces that tend to hold the particles ____________.

What can this theory explain?A) Physical States of Matter: matter can be found in three states.

___________ _____________ ____________

shape: ___________ _____________ ____________ volume: ___________ _____________ ____________

Matter can be changed from one state to another byraising or lowering the temperature. This is done byadding or removing energy.Changes that require adding energy (raising temp):D ____________________________E ____________________________F ____________________________

Changes that require removing energy (lowering temp):A ____________________________B ____________________________C ____________________________

How does the Particle Theory Explain These States: Particles in a: - gas are well separated with no regular arrangement.

- liquid are close together with no regular arrangement. - solid are tightly packed, usually in a regular pattern.

Particles in a: - gas move freely in straight lines at high speeds and only change direction when they collide with another particle.

- liquid vibrate, move from place to place, and slide past each other. - solid vibrate (jiggle) but generally do not move from place to place.

Liquids and solids are called condensed states because the particles are very close together, so the substance cannot change volume much.

Liquids and gases are called fluid states because the particles can move from place to place, so the substance can flow and change shape.

Some Characteristics of Gases, Liquids and Solids and the Microscopic Explanation for the Behavior

SOLID LIQUID GAS

retains a fixed volume and shape particles locked into place

assumes the shape of the part of thecontainer which it occupies particles can move/slide past oneanother

assumes the shape and volume ofits container particles can move past oneanother

not easily compressible little free space between particles

not easily compressible little free space between particles

compressible lots of free space betweenparticles

does not flow easily particles cannot move or slide past one another

flows easily particles can move/slide past oneanother

flows easily particles can move past oneanother

The particles do not move fastenough to overcome the attractiveforces between particles. Particlescan vibrate back and forth, but theforces always pull them back to theiroriginal place.

Particles move fast enough topartially overcome the attractiveforces. The lets them move pasteach other, but they stay in contactwith each other.

The particles vibrate and moveabout so fast that they breakaway from each other and movefreely in space.

Questions1) When we increase the temperature of a substance to change it from a solid to a liquid and then to agas, what does the extra energy do to the particles?

2) Some substances must be heated to a higher temperature to make them melt or evaporate than othersubstances. What must be different about the particles in a substance that has a higher meltingtemperature?

SNC1Pure Substances and Mixtures

All matter can be divided into two categories based on (observable) evidence.

Observations: a) When two substances are mixed, the new substance has different properties from the original substances. These substances are called ____________________ Example: salt water tastes different from pure water and looks different from pure salt.

b) In addition, the properties are variable, depending on the proportions of the mixture. Example: water tastes saltier and has a higher density if more salt is added to the same amount of water.

c) Mixtures can be un-mixed (separated) by different physical processes: i) evaporation

ii) ____________________iii) ____________________iv) ____________________

d) When mixtures are separated by physical processes into simpler substances, one eventually produces, substances that cannot be further broken down into simpler substances. These new substances have physical properties that are not variable (the same in different samples). These types of substances are called _________________ substances. Example: salt water can be distilled (the water is evaporated off and recondensed to a pure liquid)

into water and salt. The water and salt have the same basic properties each time you do this. In addition, water and salt cannot be un-mixed into any other substances.

Therefore: salt and water must NOT be mixtures.

SUMMARY: all substances can be placed into one of two categories:A) Pure Substances: properties are same from one sample to another.

cannot be separated down into other substances by mechanical means.

B) Mixtures: properties are variable from one sample to another.can be separated into other substances by mechanical means.

Given that samples of pure substances always have the same properties, where as mixtures havevariable properties (density, viscosity...) suggests an explanation based on the particle theory of matter.

3) How might the theory explain this?

4) Classify the following substance into pure substances (PS) or mixtures (M). a) Air b) Oxygen c) Sugar d) chocolate chip cookiese) sugar water f) syrup g) water h) aluminum foili) copper wire j) dusty air j) wet sand k) muddy water

How does Particle Theory of Matter explain the difference between mixtures and pure substances?

1) ObservationPure substances: ___________ properties; cannot be ___________ separated into other substances.Mixtures: __________ properties, can be ____________ separated into other substances.

ExplanationPure Substance: only one type of particle is present.

- the properties must be consistent because the same type of particle is present in each case- the substances cannot be physically separated because any particles that are removed are the

same as the ones that are left behind.

Mixture: at least two types of particles are present. - the different particles can be in any ratio, so the properties of the mixture are variable.- the substances can be physically separated because the different particle types can be

separated from each other. (one particle type may evaporate at a lower temperature, for example)

5) Which of the following substances are mixtures and which are mixtures?

A) ___________ B) ___________ C) ___________ D) ___________ E) ___________

6) Which two substances would have to be mixed to get substance D?

7) a) If substances C and D were to be separated, would you get the same pure substances?

b) What is different about substances C and D?

8) a) What is different about the particles in substance B compared to the other 4 substances?

b) Why is substance B a pure substance?

SNC1

Elements and Compounds: Two Types of Pure Substance

ObservationPure substances can be combined in certain ways to produce new substances that also are uniform andconsistent in their properties. - these new substances also must be pure substances! - since they are made by compounding other pure substances together, they are called ____________ - the processes that we use to make these new substances are called ___________ changes.

We know that pure substances have only one type of particle.We also know that in chemical changes, the reacting particles (atoms) are not destroyed, because wecan get them back in subsequent chemical changes.

ExplanationThe particles in a chemical reaction must fuse together to form a compound particle.They must do this in a particular ratio:

-the properties of a compound always are the _____________, - so the compound particles always must be the ______________.

How do we know that a new substance is created?How do we identify substances in the first place?

We look at __________________ properties.Examples:

One of the best of these for identifying substances is: ________________

This property is determined by the ______ of the particles and how _________ they are together.

Density: D = ——————

If volume is measured in mL and mass is measured in grams, the units for density are: __________

Question: can we verify that density really is a property that can be used to identify substances. Forexample, Aluminum, steel, and Silver are all shiny, grey metals. Can we use density to tell themapart?

To find out, we will perform a: _________________

Chemical and Physical Changes

Physical Changes:These are processes that combine substances into mixtures, separate mixtures, and change the objectproperties of substances. In other words, the change does not alter the particles.

e.g.: mix sand and water, chop potatoes, break a coffee mug, evaporate salt water to make pure salt and pure water, freeze water (any change in state).

Physical changes cause different types of particles to mix or separate.In a physical change, no new substances are made.

Chemical Changes: (chemical reactions) These are processes that change pure substances into other pure substances. This is the key criterion,a substance that was not present in the sample before the process starts must be present at the end ofthe process. The particles of the substance are themselves changed.

e.g.: cooking food, digesting food, burning anything.

Chemical changes cause particles to join or separate to make new types of particle.A new type of particle means a new substance.

How do you tell if a process is a chemical change or a physical change?A) Identify a new substance. This can be time consuming, but it is the only certain way.

- look for new ______________________. (examples: _______________________________)- look for new chemical _______________

- types of chemical reactions that the substance will take part in- reacts with oxygen (combustion)- reacts with water- reacts with acids or bases

B) There are some clues that suggest that a chemical change has occurred:

i) large amounts of _________ are released or absorbed (sample gets _______ or _________)example: _______________________________________

ii) a permanent ___________ change occursexample: _______________________________________

iii) a new _________ is producedexample: _______________________________________

iv) a _________ is created (___________ or fizzing)example: _______________________________________

v) a solid ____________ is made (when solutions are mixed)example: _______________________________________

vi) the process is difficult to _____________example: _______________________________________

None of these clues is fool-proof. Write down one exception for each of the clues. i) water freezes ii) paint dries

iii) melt plastic and you start to smell it iv) water boils (it is still water, just in the gas state)

v) salt precipitates when salt water evaporates vi) a coffee mug breaks