Unit 1: Matter Flashcards
Chemistry is
the science concerned with properties, composition, and behaviour of matter
- Essentially the study of matter
Mass is
the amount of matter contained in a thing
Extensive properties
qualities that are dependent on the amount of the material
Intensive properties
qualities that do not depend on the amount of material
Extensive or intensive: price of one pound of apples is $4.99
intensive
Extensive or intensive: Diya bought some apples for tonight
Extensive
KEY WORDS for determining intensive properties
if the sentence says: per pound, per gram, etc = intensive property
potential energy is
the amount of freedom particles have to move.
–> acc def: the energy of the intermolecular forces between the particles —> rmr the card about attraction and energy state
latent heat is
the heat that is being used in phase change.
Latent heat comes into the system from the outside –> which increases the PE
physical or chemical properties: Which property can be determined without changing the identity(creating a new substance) of the substance?
physical properties
chemical properties
are properties that hold the ability to change the identity of the substance –> must cause a new substance to form. they cause a reaction.
- flammability
- toxicity
- ability to oxidize
- heat of combustion
physical properties
properties that you can measure and observe without changing the substance itself. A lot of them describe the relation & interaction between matter and energy (ex, magnetic property)
- no new substance is being formed
Physical or Chemical: interactions between different forms of matter is
chemical—> produces one or more types of matter that differ from the matter before the chemical reaction
Physical or Chemical: interactions between matter and energy is
physical
subcategories of physical properties
extensive properties & intensive properties
phase is….
when you have uniform chemical properties, physically distinct, and mechanically separable
is cooking a protein a physical or chemical change?
chemical
Solid –> gas
sublimation
Gas –> solid
deposition
aqueous is when
substance is dissolved in H20
what is mechanical energy?
Kinetic Energy but for bigger objects like cars
what is kinetic energy? (4)
- the energy or any form of energy that cannot be stored
- The greater the speed and mass, the greater the KE
- particles of matter posses a type of KE called mechanical energy due to their continuous motion
- independent atoms and molecules have 3 types of mechanical energy/types of motion: vibration(back &forward motion), rotation/spinning(movement about an axis), and translation(movement from place to place).
Motion of Solid (6) from chart
- vibration motion
- packed in crystal formation, cant move past each other
- STRONG intermolecular attraction between particles
- incompressible
- fixed shape and volume
- weakest KE
Motion of Liquid (6) from chart
- vibration & rotation motion
- STILL TOUCHING EACH OTHER, not organized
- MODERATE intermolecular attraction between particles
- incompressible
- fixed volume, take shape of container
- moderate KE
Does it take more energy to go from solid to liquid or liquid to gas?
liquid to gas: bcuz it takes more effort to go from rotating to translating, than vibrating to rotating –> u are acc pulling the moecules apart
motion of gas (6) from chart
–vibration, rotation, translation motion
- NOT TOUCHING EACH OTHER, not organized
- WEAK intermolecular attraction between particles
- COMPRESSABLE
- no fixed volume of shape
- strong KE
what 2 factors cause phase change?
pressure change & temperature change
plasma
gas-like state where electrons pop off gaseous atoms to create a mixture of free electrons & cations.
- requires very high temp and low pressure to exist. –> we would not see it occur naturally on earth. matter on surface of sun=plasma
Triple point
a point at a certain pressure and temp where all 3 states of matter can exist
Critical point
- its the end point of the water/gas line
- you have one phase–> combination of gas and liquid = supercritical fluid
- chemically, it is still the same substance you started off with
triple point of water+ice+steam
0.01degrees celcius & 0.8 atm (atm=atmospheric pressure)
supercritical fluid (SCF)
- a kind of liquidy gas or gassy liquid –> not to be confused with a mixture
- can diffuse through solids like gasses but also dissolve stuff like liquids would
critical point of water+steam
374 degrees celcius & 218 atm (atm=atmospheric pressure)
RMR: things travel from ______ pressure to ______ pressure
- high to low
- a perfect vacuum would have 0 atm
ambient &/or normal pressure is
1.0 atm
does temp depend on pressure or pressure on temp
temp depends on pressure
“normal” refers to STP which is what temp and pressure
1 atm & 0 degrees celcius
if it asks for “normal” boiling point or melting point assume
assume atm=1
STP vs SATP
STP= Standard Temp & Pressure:1 atm & 0 degrees celcius
SATP= Standard Ambient Temp & Pressure: 1atm & 25 degrees celcius
Endothermic process
The system absorbs/gains energy from surroundings –> Temp of system increases & temp of surroundings decreases
Exothermic process
The system releases/loses energy to the surroundings –> Temp of system decreases & temp of surroundings increases
- humans are constantly doing the exothermic process
Thermal energy
- KE+PE
- is the energy contained within a system that is responsible for temp
Heat
flow of thermal energy from high temp object to low temp object
heat of fusion
the amount of heat required to melt a specified amount of a certain solid substance
- no change in KE, temp stays same
–> denotated with the plateau line (see page 12)
Heat of vaporization
the amount of heat required to vaporize a specified amount of a certain liquid substance
- no change in KE, temp stays same
temperature
average thermal energy (speed) of the molecules.
During phase change, energy is used to
break or weaken the interactive forces between molecules to trigger a change in state (PE is affected)
–> all energy goes towards this and therefore KE stays constant= temp stays constant
when energy is added, the particles will do one of 2 things
- speed up –> temp increases (KE increases)
- get pulled apart –> phase change (PE increases)
–> never both at the same time
As height increase atm increases or decreases
decreases
the 2 ways energy is stored
- thermal (due to motion of particles)
- phase (due to attraction between particles)
attractions increase or decrease the energy state
- decreases
- one must add energy to a system to pull particles apart
3 ways energy is transferred/added to a system
- heating (Q) –> one we look at
- working (W)
- radiating (R)
the lower the energy the more _____ the object
stable ; therefore solids are the most stable
difference between mixture & pure substance
mixture can be physically separated
difference between compound & elements
compounds can be chemically decomposed
simplest unit of matter is
atoms
- can exist under lab conditions
metalloids are
elements intermediate in properties between metals and non-metals.
- located at staircase
properties of metals (5)
- solids @ room temp except mercury (liquid, rmr hollow letters)
- ductile: can be stretched into thin wire
- metallic lustre (shiny)
-malleable: can be hammered into thin sheet - Good conductors of heat and electricity
properties of metalloids (4)
- Properties of both metals & non-metals
- metallic lustre (shiny)
- brittle: easily broken
- semi conductors of heat and electricity
properties of non-metals (4)
- Can be solid, liquid, or gas
- dull
- brittle: easily broken
- insulators
pure substances consist of only
one type of substance
- can be one element or compound
1st Group/family on periodic table
- Alkali metals
2nd Group/family on periodic table
- Alkali earth metals
3rd-12th Group/family on periodic table
- Transition metals
13th Group/family on periodic table
- Boron family
14th Group/family on periodic table
- Carbon family
15th Group/family on periodic table
- nitrogen family
16th Group/family on periodic table
- oxygen family
17th Group/family on periodic table
- halogens
18th Group/family on periodic table
- noble gases
elements 57-70 and 89-102
- inner transition metals aka rare metals
elements 57-70
- Lanthanides
elements 89-102
- actinides
Monoatomic elements
composed of only single atom: Cu, C
Diatomic elements
2 of the same atoms bonded together: H2, O2, F2, Br2, I2, N2, Cl2
Hydrogen is unique bcuz
- non-metal but behaves like a metal
- has some chemical properties of metals but mostly non-metals–> therefore considered non-metal
- hydrogen is so unique that it’s usually considered to be in its own group
Compounds have a _____ ratio
fixed
–> cant be changed
Organic & inorganic compounds
- organic compounds: consists of carbon and hydrogen atoms. can have other types of atoms.
- inorganic compounds: does not have both hydrogen and carbon
binary vs non-binary compounds
- binary compound: made up with only 2 elements ex Propane C3H8
- non-binary compound: made up of 3 or more elements ex sulfuric acid H2SO4
Ionic compound
- consists of positively charged metal ion & negatively charged non-metal ion held together by their opposite charges
- ions are packed in CRYSTAL LATTICE arrangement. SEE page 20
Molecular Compounds
consists of non-metal atoms sharing electrons
covalent bond
the shared pair of valence electrons that holds 2 non-metals together
What is a mixture?
- Combination of 2 or more different substances in no fixed ratio and not bonded together –> just blended
- substances keep their own properties and can be physically separated
Homogenous mixture
- a mixture that looks the same throughout
Solution and its parts (4)
- a homogenous mixture in which the constituent chemical species (components) do not aggregate (clump together) to form particles greater than 1 nm (1x10^9m)
-solute: the minor component, the one being dissolved - solvent: the major component of the mixture, what the solute was being disolved in
- solution is one phase, with solute evenly spread
alloys and examples
- mixture of 2 or more metals resulting in unique, desired properties
steel: iron + chromium + carbon
Bronze: copper+other metals:zinc or tin
brass: zinc+other metals
Heterogenous mixture (3)
mixture that doesn’t appear same throughout –> one or more component visible
- can be uniformly or non-uniformly mixed
- at least some particles greater than 1000nm or (1um=micrometer)
Colloid (3)
- seems to fall under heterogenous
- like solution but solute particles 1nm-1000nm –> the closer to 1000nm= more behaviour like suspension, the closer to 1nm= behaviour like solution
- appears homogenous cuz particles not large enough to settle (do not aggregate)
- include gels, sols, emulsions –> can not be separated like suspension like filtering or centrifuging
Suspension (4)
- solute particles >1000nm or 1um
- has a dispersed phase and a continuous medium. –> Dispersed phase: solute, Dispersed medium: solvent
- sediment: the large particles that settle when left undisturbed
- ex, shake before use products
Tyndall effect is
is the scattering of light by a medium containing small suspended(dispersed) particles
Tyndall effect for solutions
- light not visible through solution as solute particles are too small to reflect and scatter light
Tyndall effect for colloids
- light are visible through colloid as solute particles reflect and consequently reflect light in all directions, including into your eyes
Tyndall effect for suspension
- light not visible through solution as solute particles settle, and solvent particles too small
- to see light, either lower light source to bottom where particles settle or stir the suspension to evenly disperse the solute particles
methods of mixture separation
- components of mixture can be separated by mechanical means: picking, sifting, shaking, spinning, pouring, skimming
- Transparency test: solution & colloid transparent to diff degrees
- Filtration test: solutions not filtrable, colloids mostly not filtrable but large particles can be filtered by ultra-filtration, suspension components can be separated by ordinary filtration
- centifugation: using centripetal orbit to cause large particles to settle. the liquid can be decanted (poured off)
Particle type , properties, appearance, separation of solutions, colloids, and suspensions
PARTICLE TYPE
Solution: ions, atoms, small molecules
Colloid: large molecules or particles
Suspension: large particles or aggregates
PROPERTIES
Solution: Solute takes properties of solvent
Colloid & Suspension: immediate properties of solute and solvent
APPEARANCE
Solution: clear
Colloid & Suspension: cloudy
SEPARATION
Solution & Colloid: do not separate
Suspension: Separate to form sediment
