General Flashcards
Combustion Reaction
Heat producing reaction in which oxygen combines with another reactant, most produce more than one product including a hydrocarbon
Synthesis Reaction
When 2 or more reactants combine to form a new compound
Decomposition reaction
When a compound becomes is component parts
Single Displacement
Occurs when one element takes the place of another of the same kind
Double Displacement
When an element from a compound switches places with an element from another compound
H20 Polarity
Oxygen is slightly negative which attracts the slightly positive ions.
Hydrogen is slightly positive which attracts the slightly negative ions.
Total Ionic Equation
Lists all aqueous solutions as individual ions rather than compounds
Precipitates are listed as compounds
Net Ionic Equation
All ions that have not undergone a chemical reaction are removed from both sides of the equation
Flame Test
Elements are exposed to heat allowing them to absorb energy and move to a lower or higher shell and when they return to their normal state, energy is released in the form of light
Different elements produce different colours
Emission Spectra
Electricity can be passed through elements to produce a flash of light which gives off a specific banding pattern
Solubility
An aqueous solution is combined with another aqueous solution to potentially produce a precipitate
Infrared Spectroscopy
Uses the constant movement of molecules to detect frequencies which indicate the presence of those molecules
Structural isomers
When 2 compounds have the same formula but different structures
Alkanes
Contain only single carbon to carbon bonds.
Prefix is determined by the number of carbon elements in the parent chain.
Branches are added to the front of the name with the size, number (di-, tri- etc) and location.
Suffix ‘-ane’
Alkenes
Contain at lease one carbon to carbon double bond.
Double bond location is marked.
Prefix is determined by the number of carbon elements in the parent chain.
Branches are added to the front of the name with the size, number (di-, tri- etc) and location.
Suffix ‘-ene’
Alkynes
Contain at lease one carbon to carbon triple bond.
Triple bond location is marked.
Prefix is determined by the number of carbon elements in the parent chain.
Branches are added to the front of the name with the size, number (di-, tri- etc) and location.
Suffix ‘-yne’
Combustion of a Hydrocarbon
Products: energy in the form of heat, water, carbon dioxide.
If combustion is incomplete, pure carbon will be released as well.
Substitution Reaction of Hydrocarbons
Requires a catalyst.
A hydrogen atom is replaced by another atom or group of atoms.
Non-Polar vs Polar vs Ionic
If the difference in Electronegativity (EN) is less than 0.5, the compound is non-polar
Between 0.5 and 1.7, Polar
Above 1.7, the bond is ionic
Alcohol Functional Group
Contains one carbon atom bonded to a hydroxide molecule
Suffix is ‘-anol’
The location of the hydroxide is marked
Primary: hydroxide is bonded to a carbon which is bonded to only one other carbon atom
Secondary: carbon atom is bonded to 2 other carbons
Tertiary: carbon atom is bonded to 3 other carbon atoms
Ether Functional Group
An oxygen atom is bonded to 2 carbon atoms or hydrocarbon chains
Infix ‘-oxy-‘ added between the carbon chains
Aldehyde
Contains an oxygen atom double bonded to a carbon atom (carbonyl group)
Suffix is ‘-anal’
The numbering or branches etc. starts at the carbonyl group
Ketone
Contains an oxygen atom double bonded to a carbon atom, the carbon atom is bonded to 2 other carbon atoms (is inside the carbon chain, not on the end)
Location of the carbonyl group is marked
Suffix is ‘-anone
Carboxylic Acids
Contains a carbon atom double bonded to an oxygen atom and bonded to a hydroxyl group. (they’re both connected to the same carbon atom)
Suffix is ‘-anoic acid’
Can hydrogen bond
Ester
Contains a carboxylic group (carbon atom double bonded to an oxygen atom and bonded to a hydroxyl group.) but the hydrogen in the hydroxide is replaced with another carbon atom/chain
Suffix is ‘-anoate’
Amines
Consists of a Nitrogen atom bonded to at least one carbon atom or carbon chain
Nitrogen atom has max 2 hydrogens and min 1 hydrocarbon chain bonded to it
‘amino-‘ is added to the front of the parent chain
N- is added to the name of the compound if there is a branch on the Nitrogen atom
Primary: hydroxide is bonded to a carbon which is bonded to only one other carbon atom
Secondary: carbon atom is bonded to 2 other carbons
Tertiary: carbon atom is bonded to 3 other carbon atoms
Flammability/Combustability
Determined by a substances flashpoint
Flashpoint is the lowest temperature at which a combustable mixture can form in the air near the substance
Volatility
How readily a substance vaporizes
Isotope
An atom which has an unequal number of neutrons and protons
Atomic Mass Formula
(% abundance)(atomic mass of isotope 1) + (% abundance)(atomic mass of isotope 2) +…
Calculating Moles
n=N/NA
n=number of moles
N=number of formula units
NA = 1 mole (6.022*10^23)
Molar Mass
Atomic mass is g/mol
Molar mass is all of the atoms added together
Converting Moles to Mass
n=m/M
n=number of moles
m=mass in grams
M = molar mass
Concentration V per V
(volume of solute/volume of solution)*100
Gives a percentage
Concentration M per V
(mass of solute/volume of solution)*100
Gives a percentage
Molar Concentration
moles per Litre c=n/V c=concentration n=number of moles V=volume in L
Stoichiometry
Calculations using ratios
Ratios are calculated in moles, values all need to be converted to moles
The total mass of reactants equals the total mass of products
Limiting Reagent
One reagent does not have a mass equivalent to the others (based on ratios)
8 tires, 2 engines and 1 car body can only make 1 car
Car body is the limiting reagent
Calculate maximum possible yield for each, lowest possible yield indicates limiting reagent
Percent Yield
(actual yield/theoretical yield)*100
Water recycling
Evaporation
Condensation (water condenses into clouds to become precipitation)
Precipitation
Surface runoff into bodies of water
Hydrogen Bonding in Water
There is an attraction between the hydrogen atoms in one molecule of water and the oxygen atoms of another (hydrogen bonding)
Raises the boiling point and results in high surface tension
Specific Heat Capacity
The amount of energy required to heat the substance 1 degree Celsius
Distilled water
Water is boiled to create pure H2O
Water Hardness
Hard water is from high calcium and magnesium content
Ion Exchange Water Softener
Device Contains a canister of a large organic polymer resin with lots of sodium ions
Resin attracts the calcium and magnesium and they are replaced by the sodium ions
Dissolved Oxygen
Aquatic life depends on dissolved oxygen
Some comes directly from the atmosphere
Some comes from aeration from crashing waves
Aquatic plants can provide oxygen as well
If concentration is below 4ppm, most fish cant survive
Physical Contaminants
Usually solids which are insoluble
Most can be removed by filters
Liquid contaminants are hard to remove
Chemical Contaminants
Any liquid or solid chemicals that get dissolved in water
Many come from humans
Some chemicals are added for health or purification (fluoride and chlorine)
Biological Contaminants
Microorganisms in the water that could be harmful (bacteria and viruses)
E. Coli is a well known one
Boiling can remove it
Water Treatment
Intake: water is chlorinated to kill microorganisms
Coagulation: a chemical such as aluminum sulphate is added which forms small sticky particles called floc for dirt to stick to
Flocculation: as dirt builds up on floc, it becomes heavier and larger
Sedimentation: floc settles or is filtered, water passes through activated carbon, sand and gravel
Filtration: activated carbon filters
Disinfection: chlorinated to kill microorganisms
Fluoridation: fluoride compounds are added to help prevent tooth decay
Distribution:
Acids
IONIZE Strength determined by the extent to which they ionize (100% is strongest) Concentration is mol/L Taste sour Good conductors of electricity (polarity splits up the acids into ions) react with active metals Change colours of acid-base indicators React with carbonate compounds Neutralize acids
Bases
DISSOCIATE Strength determined by the extent to which they dissociate (100% is strongest) Concentration is mol/L Taste bitter Feel slippery Good conductors of electricity Change colours of acid-base indicators Neutralize acids Release hydroxide ions
pH
0 is most acidic
14 is most basic
7 is neutral
blood contains a buffer to maintain pH
Titration
Used to detect the concentration of a known acid of unknown concentration
Either a pH meter or an acid-base indicator is used to detect pH
When the pH reaches a desired level, calculate the moles of base added to the solution based on concentration
Moles of base added = moles of acid present when the solution is neutral
The concentration of the original solution = mol/L
Sulphuric Acid Precipitation
Sulphur dioxide - smelting ores with suplur in them sulphur dioxide -> sulphuric acid 2SO2 + O2 -> 2SO3 2SO3 + H20-> H2SO4 (sulphuric acid) This can cause the acid to fall in the form of rain
Nitric Acid
By-product of the combustion of fuels
N2 + O2 -> 2NO
2NO + O2 -> 2NO2
3NO2 + H2O -> 2HNO3 (nitric acid) + NO
Environmental Effects of Acid Precipitation
Most aquatic life cannot withstand decreases in pH
A basic substance can be added to neutralize the effects
Better to remove the source
Smokestack Scrubbers
CO2 and CaO are added to the combustion chamber so that some of the SO2 reacts and becomes CaSO3 which falls out of the air
The air is then sprayed with an aqueous solution of CaO to remove the majority of the remaining SO2
Catalytic Converter
Uses palladium or platinum honeycomb structure as a catalyst which speeds up the decomposition of Nitrogen oxide
Troposphere
Lowest 10km where weather occurs
Stratosphere
10-40km low oxygen density but ozone begins to form. air temp is warmer due to O3 absorbing sun heat
Mesosphere
40-100km, where meteorites burn up
Thermosphere
100-500km orbiting spacecrafts
Exosphere
adjacent to space
Air composition
78% Nitrogen
20.9% Oxygen
1% other (mostly CO2)
Greenhouse effect
Certain GHGs are better than others at absorbing heat energy from the sun
Normal matter cycles kept it stable, but humans producing CO2 offset the balance
Climate Change Trends
The tilting of the earths axis affects the climate
Ozone layer
Has been depleted by Chlorofluorocarbons (CFC, not naturally occuring
Hole found over the north pole
Primary air pollution
Produced as an immediate and direct result of human activity
- combustion of fossil fuels
- smelting of ores
VOC (volatile organic compounds)
substances that readily evaporate from organic compounds
Particulate matter: any type of fine dust that is an irritant when inhaled
Secondary air pollutant
result from reactions from primary air pollutants
Air Quality Index (AQI)
Lists the worst pollutant on a given day and ranks it from 0 to 120
pollutants: Carbon Monoxide, Nitrogen dioxide, ozone, sulphur dioxide, suspended particles, total reduced sulphur
Air Quality Health Index (AQHI)
4 Key Pieces of Info
- a number that outlines the health risk (1-10)
- a description of the health risk
- Current and forecasted AQHI readings
- Health messages for the general population and those at risk
Oxidization Reduction reaction
Oxidization: element loses electrons
Reduction: element gains electrons (reduces in charge)
classified as a synthesis reaction
Corrosion
The deterioration of a metal due to a redox reaction
Zinc is used to coat steel to prevent rust (zinc forms a protective coating due to a redox reaction)
Rusting
Used to describe the corrosion of iron and iron alloys
Both oxygen and water are required for rust to occur
Protective coatings can protect metal
2 types of cathodic protection
Impressed current: involves pumping electrons into the metal continually from an external power source
Sacrificial Anode: attach the metal to another metal which is more easily oxidized
Voltage
The energy difference between two points in the cell
-all cells made of the same material have the same voltage
some last longer because they have more chemicals
Current
Measures the flow rate of electrons per second
Larger cell=more current
Electrolysis
The process by which electrical energy is used to make a non-spontaneous reaction occur
