Definitions Flashcards
Ion
Atom which has lost or gained electrons
isomer
Same molecular formula Different structural formula
Hydrocarbon
Compound containing only C and H
Acid
Solution containing a higher number of H+ aqueous ions than OH- aqueous ions
Molecule
2 or more atoms joined together by covalent bonds
Covalent bond
A shared pair of electrons
Isotope
Same atomic number Different mass number
Alkali
Solution with higher numbers of OH- aqueous ions than H+ aqueous ions
Atomic number
Number of protons in an atom
Fuel
A substance that burns to release energy
Combustion
Combining with oxygen to release energy
Valency
The number of unpaired of outer electrons
Element
Substance containing only one type of atom
Mass number
The sum of the number of protons and neutrons in an element
Solute
A substance that will dissolve in a liquid (water)
Diatomic
A molecule containing two atoms
What are the 7 diatomic elements
Iodine Hydrogen Nitrogen Bromine Oxygen Chlorine Fluorine
Electrolyte
An ionic solution used to complete an electrochemical cell
Exothermic
A reaction that releases energy
Endothermic
Reaction in which heat energy is taken in
What are the properties of protons
Charge : 1+ Mass: 1 a.m.u Found: in the nucleus
What are the properties of neutrons
Charge: 0 Mass: 1 a.m.u Found: in the nucleus
What are the properties of electrons
Charge: 1- Mass: 0 Found : in shells around nucleus
Period
Horizontal row of elements in the periodic table
Electricity
The flow of charged particles(electrons and ions)
Solvent
A liquid into which a substence will dissolve
Homologous series
Compounds with Same general formula Similar chemical properties
Lattice
A regular, repeating 3-D structure
Saturated
A substance where all C to C bonds are single
Unsaturated
A substance contains (at least) on C=C bond
Monomer
Small unsaturated molecule that takes part in addition polymerisation
Halogen
Any of the group 7 elements
Alkali metal
Any of the group 1 metals
Salt
When the H+ aqueous ions of an acid are replaced by metal (or ammonium) ions
- sulphuric acid gives sulphate salts
- hydrochloric acid gives chloride salts
- nitric acid gives nitrate salts
Neutralisation of acids
Removing excess H+ aqueous ions from a solution
Base
A substance that neutralises an acid
What are the 4 types of base
Metal Metal Hydroxide Metal Carbonate Metal Oxide
Pollution
The introduction of harmful substances into the environment
Haber Process
Industrial process used to manufacture ammonia
Fertiliser
A soluble salt containing N, P, or K
Spectator ion
An ion that doesn’t take part in a reaction Reactions of acids Displacement reactions
Catalyst
A substance that increases the rate of a reaction
What are the ideal conditions for Haber Process?
Temperature: around 450 degrees Pressure: 200 atmospheres Catalyst: Iron
Indicator
A substance that changes colour when something is added to it
Solution
A mixture of a solvent and a solute
Electrolysis
Breaking apart a compound using electricity
What is an ion bridge?
Used to complete the circuit
Why are some nuclei unstable?
The neutron to proton ratio is outwith band of stability
Noble gases
Unreactive group 8 elements
Ion migration
Movement of ions to opposite charged terminal
A mole
The gram formula mass of a substance
Relative atomic mass (RAM)
The average mass of an element taking into account the relative abundance of each isotope
Density
Mass divided by volume
Electrostatic attraction
Attraction between oppositely charged particles
Thermoplastic polymer
Can be reshaped upon heating
Thermosetting polymer
Is decomposed upon heating
Biodegradable
Broken down by the action of bacteria
Nitrogen fixing
Turning nitrogen into a soluble form (nitrates!!)that plants can take in through their roots
Acid rain
Rain with pH below 5.5
Acidic oxide
Non metal oxide that is soluble in water
Basic oxide
Metal oxide that is soluble in water
Corrosion
The changing of the surface of a metal from an element into a compound
Oxidation
The loss of electrons
Reduction
The gain of electrons
Functional Group
The part of a molecule that is responsible for its chemical (and sometimes physical) properties.
Why are atoms neutral
They contain equal numbers of positive charges (protons) and negative charges (electrons)
Qualitative Analysis
Used to determine what substances are present. A flame test for example
Quantitative Analysis
Used to determine the quantity of a substance in a sample. A titration is used for quantitative analysis
What are the steps in the nitrogen cycle?
Eutrophication
Water systems enriched become by nutrients from fertliser run-off
What are the steps in eutrophication?
- Excess nutrients from fertilisers get into water systems (lakes etc) by natural run off or rainfall
- High levels of nitrates cause excess algal growth.
- Algal growth blocks out sunlight needed by plants below water
- Bacteria use oxygen as they feed on dead plants
- Reduced O2 levels kills off marine creatures
Nitrates and blue baby syndrome
Nitrate effect on human health
What are P K and N needed for and what problems can deficiency cause?
Why can alkalis never have zero H+ ions present
Because alkalis are aqueous solutions and the dissociation of water means some H+ ions must be present
Why can acids never have zero OH- ions present
Because acids are aqueous solutions and the dissociation of water means some OH- ions must be present
Give 2 advantages of neutralising with a metal carbonate instead of a metal oxide
- Reaction rate is high enough that acid doesn’t need to be heated
- Easier end point detection due to evolution of CO2
