Unit 1 – Matter
Some Basic Definitions:
Qualitative
non-numeric information often based on observation
Quantitative
numeric measurable information
Observation
qualitative information
Interpretation
an attempt to put meaning to an observation
Description
a list of properties of something
Data
quantitative information that is experimentally determined
Experiment
a test or procedure that is carried out to discover a result
Hypothesis
a single, unproven assumption which attempts to explain a natural phenomenon
Theory
is a set of hypothesis that ties together a large number of observations into a logical consistent
and understandable pattern. It is a theory that has been TESTED and REPLICATED successfully many times
Law
is a broad generalization or summary statement which describes a large amount of experimental
evidence stating how nature behaves wen a particular situation occurs. It has been “proven”
Answer the following questions:
1.
2.
3.
Give both a qualitative and a quantitative description of a) a length of time b) a temperature
a) Soon, 5 min b) warm, 24C
( qualitative, quantitative) Copper is a reddish-colored element with a metallic lustre. It is an excellent conductor of heat and electricity,
melts at 1085C and boils at 2563C. Archeological evidence shows that is has been minded for the past 5000 years and presently is
considered to be one of the most important metals available. Copper is insoluble in water and virtually all other solvents, reacts easily
with nitric acid but only slightly with sulphuric acids. Its density is 8.92g/mL, which makes is more dense that iron.
What is the difference between a) observation and data, b) hypothesis and theory c) theory and law. A) observations are qualitative and
data is quantitative b) confidence is low in an hypothesis but high in a theory. Hypothesis attempts to explain one experiment, theory
results from may experiments c) theory is not or can not be proven, however a law can and has been. Laws describe what will happen in a
known situation, but a theory attempts to explain a wide range of experimental results.
The Physical Properties of Matter:
Matter:
anything that has mass and occupies space
Chemistry: is the science concerned with the properties, composition, and behaviour of matter
Substance: is something with a unique and identifiable set of properties (diff properties = diff substance)
Physical Property: is a property of a substance that can be found without creating a new substance
Ex. Density, color, hardness, mp, bp
Chemical Property: is the ability of a substance to undergo chemical reactions and change into new substances
either by itself or with other substances
Ex. Hydrogen burns in air
Intensive Property: physical property that depends solely on the nature of the substance NOT how much is present
Ex. density, mp, bp,
Extensive Property: physical property that depends on the amount of the substance present
Ex. mass, *** are not used to identify the substance
Answer the following questions:
1.
2.
Which of the following describes physical or chemical properties a) glass is transparent physical b) salt melts at 801C physical c)
adding lye to fat makes soap chemical d) copper conducts electricity physical e) fumes from ammonia and hydrochloric acid mix to
produce a white smoke chemical
Which are intensive or extensive properties: a)shape b)smell c)length d) color e)electric conductivity f)time required to dissolve a
solid g) hardness intensive = b, d, e, g, and extensive = a, c, f
Matter exists in three common states or “phases” each of which has a unique set of properties
Phase or State
Solids
Properties
Rigid
Don’t readily change shape
Very small changes to volume when
heated or pressure = Not compressible
Conform to the shape of their container
Very small changes to volume when
heated or pressure =Not compressible
Liquids
Gases
Conform to the shape of their
containers
Compressible – drastic changes in
volume when heated or pressure
Molecular Dispersement
Particles are packed into a given volume in a
highly organized rigid manner which requires
the particles to be in direct contact with one
another.
Particles are in close contact with one another
but have enough room to slide past one
another easily and prevent an organized
packing
The particles are widely separated and only
contact each other in collisions
Liquids are an “intermediate” phase between solids and gases because:


Like a gas because conform to space of container
Like a solid because not compressible
Other Definitions you need to know:
Hardness: ability of a solid to reseit abrasion or scratching
Malleability: :
ability to be rolled or hammered into thin sheets
Ductility: : ability to be stretched or drawn into wires
Lustre: :
the manner in which a solid surface reflects light - metallic, glassy, oily, pearly, silky, dull
Viscosity: : the resistance to a fluid flow
Diffusion: : the intermingling of fluids as a result of motion within the fluid (liquids and gases
Vapour: :
the gaseous material formed by the evaporation of a substance which boils above room temperature
Boiling Point: : the temperature at which a liquid changes to a solid
Melting Point: : the temperature at which a solid changes to a liquid
Answer the following Questions:
1.
2.
3.
Compare the relative boiling points of ionic and covalent compounds? Ionic compounds havehigh boiling points compared to covalent
compounds
What are intermolecular and intramolecular bonds? An intramolecular force is any force that holds together the atoms making up
a molecule or compound. They contain all types of chemical bond. They are stronger than intermolecular forces, which are present
between atoms or molecules that are not actually bonded.
Explain your answer to question 1, using the terms defined in question 2. – The boiling point is essentially the temperature at which there
is enough kinetic molecular energy to separate the molecules farther from one another so that they are in a gas state. This temperature
essentially must overcome the intermolecular forces between the molecules which are stronger between ionic compounds that covalent
compounds. Recall that ionic compounds contain positive and negative ions. This results in them having not only intra but also intermolecular attractions which must be overcome with kinetic energy in order to have them spread apart (change phase).
Classification of Matter:
System:_is the part of the universe being studies in a given situation
Phase:___is any part of a system which is unitform in both its compositions and properties
Element: is a substance which cannot be separated into simpler substances as a result of any chemical process
Ex. silver metal, Copper metal, hydrogen gas
Atom
is the smallest possible unit of an element which retains the fundamental properties of the element
Ex. silver (Ag) Copper (Cu) Hydrogen (H)
Molecule is a cluster of two or more atoms held together strongly by electrical forces
Ex. water, ethanol, table sugar
Ion
an atome or molecule which possesses an electric charge
Ex. sodium ion, nitrate ion
Particle
is a general erm used to describle a small bit of matter such as an atome, molecule or ion
Homogeneous has uniform unchanging physical properties
Ex. 1L or an aqueous solutions which has a consistant clarity and density of 1.035g/mL throughout.
Heterogeneous the substances making up the mixture will each have their own, unique set of properties
Ex. water and iron mixture, both maintain their unique density and boiling points
Pure substance
unchanging uniform physical properties
Ex. mercury in a thermometer
Mixture
a system made up to two or more substances such that the relative amounts of each can be varied
Ex. salt dissolved in water
Mechanical mixture is a heterogeneous mixture
Ex. gravel, a pencil
Solution
a homogeneous mixture of two or more substances
Ex. air, soda pop, alloys
Solvent
component in a solution which exists in the greater quanitity
Ex. salt dissolved in water  water is the solvent
Solute is the component in a solution which exsists in the smaller quantity
Ex. the salt
Compound is a pure substance make up of two or more types of atoms but there is only one type of molecule in a
compound Ex. sugar, salt, water
Separation of Substances:
Miscible: two liquids that are mutually soluble in each other in all proportions
Immiscible:
two liquids that are insoluble in one another
Synopsys of Separations Methods – (refer to last day’s notes)
Mechanical Mixtures:
MIXTURE
Solid in Solid
METHOD
Hand Separation
Gravity Separation
Solvent Extraction
WHEN TO USE THE METHOD
Large chunks present among other
solids
The density of desired solid is much
diff from the other solid
One solid preferentially dissolves in a
particular solvent
Chromotography
Solid in Liquid
Hand Separation
Gravity Separation
Filtration
The solids are colored, present in small
amounts and soluble in some solvent
A few large pieces of solid are present
in the liquid
Solid particles are preens tin small
amount of liquid
Solid particles are present in a large
amount of liquid
Solutions:
MIXTURE
Solid in a Liquid
METHOD
Evaporation
Distillation
Solvent Extraction
Solid in a liquid Con’t
Recrystallization
Chromotography
Liquid in Liquid
Distillation
Solvent Extraction
WHEN TO USE THE METHOD
The solid is wanted and the liquid is
not
The liquid is wanted, the solid may not
be
An immiscible added solvent
preferentially dissolves at least one
but not all solids
One dissolve solid is much less soluble
that the others (liq not wanter)
Small amounts of more that one
colored solid are present (liq not want)
Two or more liquids are present and
have different boiling temperatures
In immiscible added solvent
preferentially dissolves at least one
but not all of the liquids present
Phase Changes:
Watch video: http://www.youtube.com/watch?v=KCL8zqjXbME
Chemical Change: is a change in which a new substance is formed with a new set of properties
Physical Change: is a change in the phase of a substance such that no new substance is formed
** Chemical changes are frequently accompanied by physical changes
Melting temperature solid to liquid
Freezing temperature liquid to solid
Boiling Temperature liquid to gas
Condensation gas to liquid
On the sloping portions of the graph: all the heat is used to warm the substance so the temperature rises
the heat is going directly into increasing the kinetic molecular energy of the compound and thus the temp increases
On the level portions of the graph:
the heat added is used to break up the solid and allow the liquid to form. A
better way to say this is that the energy is being used to break the attraction between the molecules rather that adding
kinetic energy to them which we see as an increase in temperature
Sublimation:
solid to gas
Deposition:
gas to solid
Kinetic Energy’s Role in Physical Change:
Watch: http://education-portal.com/academy/lesson/changes-in-heat-and-energy-diagrams.html#lesson
Temperature
Energy Kinetic Energy – the energy molecules possess as a result of their motion
Heat Heat is the total energy of molecular motion in a substance while temperature is a measure of the average energy of
molecular motion in a substance. Heat energy depends on the speed of the particles, the number of particles (the size
or mass), and the type of particles in an object. Temperature does not depend on the size or type of object. For
example, the temperature of a small cup of water might be the same as the temperature of a large tub of water, but
the tub of water has more heat because it has more water and thus more total thermal energy.