N5 Flashcards
How are elements in the periodic table arranged?
In order of increasing atomic number
What can the periodic table be used to determine
Whether an element is a metal or non metal
What does a nucleus contain
Contains protons neutrons and electrons that orbit the nucleus
Protons charge ?
1positive
Charge if neutrons?
Neutral
Electron charge?
1 negative
What has the approximate mass of 1 atomic mass unit
Protons and neutrons
How do u know the number of protons given from an atom
Is given by the atomic number
In a neutral atom the number of electrons is eaqual to the…?
Number of protons
The mass number of an atom is equal to….?
The number of protons added to the number of neutrons
What are isotopes defined as
Atoms with the same atomic number but differnt mass numbers
What is nuclide notation used to show?
Atomic number
Mass number
Charge of atoms from which the number of protons electrons and neutrons can be determined
How many isotopes do elements normally have
1 or 2
How was the average atomic mass calculated for each element ?
And what are the values known as
By using the mass and proportion of each isotope present
These are known as relative atomic masses
What forms between non metal atoms
Covalent bonds
When do covalent bonds form ?
When 2 positive nuclei are held together b their common attraction for a shared pair of elements
What are the 7 diatomic elements
Hydrogen
Nitrogen
Oxygen
Fluorine
Chlorine
Bromine
Iodine
What does the shape of covalent molecules depend on
Number of bonds and the orientation of these bonds around the central atom
What are the 4 shapes of covalent molecules
Linear
Angular
Trigonal pyramidal
Tetrahedral
What does more than 1 forming between atoms lead to
Double or triple covalent bonds
What can covalent substances form?
Discrete molecular or giant network structures
Covalent molecular substances have strong….?
Covalent bonds within the molecules and only weak attractions between the molecules
Covalent molecular substances have low….?
Melting and boiling points as only weak forces of attraction between the molecules are broken when a substance changes state
Covalent molecular substances have a network of……?
Strong covalent bonds within one giant structure
Covalent molecular substances do not conduct…?
Electricity because they do not have charged particles which are free to move
Covalent molecular substances which are…?
Insoluble in water may dissolve in other solvents
Covalent network structures have a network of…?
Strong covalent bonds within a giant structure
Covalent network structures have very high…?
Melting and boiling points because the network of strong covalent bonds is not easily broken
Covalent network structures do not….?
Dissolve in general
Covalent network substances do not…?
Conduct electricity this is because they do not have charged particles which are free to move
When are ions formed
Ions are formed when when atoms lose or gain electrons to the stable electron arrangement of a noble gas
In general metal atoms lose……?
electrons forming positive ions and non metal atoms to gain electrons forming negative ions
What are ionic bonds .?
Are the electrostatic attraction between positive and negative ions
Ionic compounds form…?
Lattice structures of oppositely charged ions with each a positive ion surrounded by negative ions and each negative ion surrounded with each positive ions
Ionic compounds have high…?
Melting and boiling points because strong ionic bonds must be broken in order to break up the lattice
Many ionic compounds are..?
Soluble in water
What happens as ionic compounds dissolve ?
The lattice structure breaks up allowing water molecules to surround the separated ions
Ionic compounds can … only when molten or in solution
Conducts electricity
How can conduction be explained in ionic compounds ?
By the movements of ions towards oppositely charged electrodes
What are compound names derived from
From the names of the elements from which they are formed
What does a compound ending ide mean
It contains 2 elements
What does compound ending in ite or ate mean
It has oxygen in it
What are group ions ?
Ions containing more than one type of atom
What is the mass of a mole in grams equal to
To the gram of formula mass can be calculated using relative atomic masses
What is formed when a solute is dissolved in a solvent
A solution
What is the ph scale an indication of?
Hydrogen ion concentration and runs from 0-14
What does a neutral solution have equal of
H+ and OH- ions
What ph is water
Neutral
As it dissociates producing equal concentrations of hydrogen and hydroxide ions at any time
The symbol of 2 arrows represents what
That the reaction is reversible and occurs in both directions
Acidic solutions have a higher….?
Concentration H+ions than OH-and have ph below 7
Alkaline solutions have higher…?
Concentration of OH- ions than H+ ions and have a ph above 7
Dilution of an acidic solution with water will…?
Decrease the concentration oh H+ and the ph will increase towards 7
Dilution of an alkaline solution with water will …?
Decrease the concentration of OH- and the ph will decrease towards to 7
Soluble non metal Oxides will….?
Dissolve in water to forming acidic solutions
Soluble metal oxides…?
Dissolve in water to form alkaline solution
What neutralises acids
Name some ?
Bases
Metal oxides ,metal hydroxides, metal carbonates
What is a neutralisation reaction ?
Which a base reacts with an acid to form water
What does the name of a salt produced depend on
On the acid and base used
What does hydrochloric acid produce
Chlorides
What does sulphuric acid produce
Sulphates
What does nitric acid produce
Nitrates
What are spectator ions
Ions that remain unchanged by the reaction
What can an indicator do at the end of an experiment
Be added to show the result
What does titration do
Produce a soluble salt
What is used to produce soluble salts
Insoluble metal carbonates and insoluble metal oxides
What are reactants
The chemicals you start a reaction with
How can you speed up a chemical reaction?
Heating them up
Increasing the surface area
Add a catalyst
Increasing concentration
Formula for average rate
/\quantity
—————
/\ time
What is an element ?
A substance made up of the same type of atom
What is an isotope
Atoms of the same element which have differnt mass snumbers but same atomic number
How do elements in groups 1-7 become stable like elements in group 8
By sharing electrons
Transferring electrons
Where does ionic Bonding occur
Between non metals and metal
Some examples of ionic compounds ?
Sodium chloride
Copper sulphate
Sodium hydroxide
What state are ionic compounds at room temperature
Solid
Mono means ?
1
Di means
2
Tri means
3
Tetra means?
4
Penta means?
5
Hexa means
6
Hepta means?
7
SVISS how to produce an ionic formula ?
(S)ymbols down
(V)alency under symbol
(I)nclude charge
(S)wap valency
(S)implify valency if possible
Name some common acids
Hydrochloric acid
Sulfuric acid
Nitric acid
Formula for hydrochloric acid ?
HCL
(H+Cl-)
Formula for sulfuric acid
H2SO4
((H+)2SO2-4)
Formula for nitric acid
HNO3
(H+NO3-)
Name some common bases
Sodium hydroxide
Potassium hydroxide
Sodium carbonate
Formula for sodium hydroxide
NaOH
(Na+OH-)
Formula for potassium hydroxide
KOH
(K+OH-)
Formula for sodium carbonate
Na2Co3
((Na+)2Co2-3
Word equation for how to make a base
Metal oxide +water ->metal hydroxide
Word equation for how to make an acid
Non metal oxide + water -> acid
What is metallic bonding
Electrostatic attraction between 2 positively charged ions and delocalised electrons
Why are metallic elements conductors
They contain delocalised electrons
What can metals be used to produce
Soluble salts
What is reduction in metals
A gain of electrons in a reactant in any reaction
what is oxidation in metals
A loss of electrons by a reactant in any reaction
What happens in a redox reaction
Reduction and oxidation takes place at the same time
What happens during the extraction of metals
Metal ions are reduced forming metal atoms
What are the methods to remove a metal from an ore
Heat alone
Electrolysis
heat + C/CO
What is electrolysis
The decomposition of the ionic compound into its elements using electricity
What happens to ions in electrolysis
Positive ions gain electrons at the negative electrode and negative ions lose electrons at the positive electrode
What are electrolytes
Solutions that conduct electricity containing ions
How can a simple cell be made
By placing 2 metals in an electrolyte
What does growing plants require
Nutrients
What must a fertiliser contain to be effective
Nitrogen
Phosphorus
Potassium
What are fertilisers
Substances which restore elements , essential for healthy plant growth
What are ammonia and nitric acid important for
To produce soluble nitrogen contains salts (fertilisers)
Describe ammonia
Pungent clear colourless gas which dissolves in water
What happens if u dissolve ammonia in water
It produces an alkaline solution
What is the Haber process
Production of ammonia required for fertiliser production
What is the catalyst used in the haber process
Iron
What is the starting material for the production of nitric acid
Ammonia
What does the Ostwald process use
Ammonia
Oxygen
Water
What is the catalyst used in the Ostwald process
Platinum
What does radioactive decay involve
Changes in nuclei of atoms
How can radioisotopes become more stable
By giving out alpha, beta or gamma radiation
Alpha particles consist of?
2 protons and 2 neutrons and carry. A double positive charge
What stops alpha radiation
A piece of paper
Alpha particles will be attracted towards…..
Negatively charged plates
What are beta particles
Electrons ejected from the nucleus of an atom
What stops beta rays of radiation
A thin sheet of aluminium
Beta particles are attracted to…..
Towards a positively charged plate
What are gamma rays
waves emitted from within the nucleus of an atom
What can stop gamma rays
Barriers like lead or concrete
Gamma rays are not….
Deflected by an electric field
What are the 3 radiation types
Gamma alpha beta
How can an alpha particle be represented
4
He
2
How can a beta particle be represented
0
e
-1
How can proton be represented
1
P
1
How can a neutron be represented
1
n
0
What is a half life
The time for half of the nuclei of a particular isotope to decay
The half life of an isoptope is a constant
What does this mean?
It is unaffected by chemical or physical conditions
What can be used to date materials
Radioactive isotopes
How do you determine a half life of an isotope
For a. Graph showing a decay curve
what has a range of uses in medicine and in industry
radioisotopes
what are plastics
materials known as polymers
what are polymers
a long chain of molecules formed by joining together a large number of small molecules called monomers
what does unsaturated mean
that there’s a double bond
what is the name given to a chemical reaction in which unsaturated monomers are joined, forming a polymer
addition polymerisation
what is a reapeating unit
the shortest section of polymer chain which, if repeated, would yield the complete structure of a polymer
what is a homologous series
a family of compounds with the same general formula and similar chemical properties
the subsequent members of homologous series show a….
general increase in their melting and boiling points
what is the pattern attributed to
increasing strength of the intermolecular forces as the molecular size increases
what are hydrocarbons
compounds containing only hydrogen and carbon atoms
what does saturated mean
compounds containing only single carbon-carbon bonds
what does unsaturated mean
compounds contaning at least 1 carbon-carbon double bond
how do you disdinguish unsaturated compound from a saturated one
with bromine solution
what happens when you add bromine solution to an unsaturated compound
it decolourises it
what are isomers
compounds with the same molecular formula but different structural formula
isomers may belong to ……
different homologous series
isomers usually have different….
physical properties
what are alkanes
homologous series of unsaturated hydrocarbons
what is a use of alkanes
fuels
what happens to an alkane in water
nothing , its insoluble
what is the general formula for alkane
CnH2n+2
what are cycloalkanes
a homologous series of saturated , cyclic hydrocarbons
what are cycloalkane uses
fuels and solvents
what is the general formula for cycloalkanes
CnH2n
what are alkenes
homologous series of unsaturated hydrocarbons
what are the functions of alkenes
made to make polymers and alcohols
what is the alkenes functional group
the c=c double bond group
what is the general formula for alkenes
CnH2n
what are the addition reactions
hydrogen forming alkanes - hydrogenation
halogens forming dihhaloalkanes
water forming alcohols - hydration
what are some functions of alcohols
fuels
solvents
perfumes
methanol, ethanol and propanol are miscible in water this means …..
the solubility decreases as size increases
as alcohols increase in their melting and boiling points increase due to?
increasing strength of the intermolecular forces
what is an alcohol
a molecule containing a hydroxyl functional group - OH group
what is the general formula for alcohols
CnH2n+1OH
how are carboxylic acids used
in the preparation of soaps and preservatives and medicines
what is vinegar
and what is its formula
a solution of ethanoic acid with molecular formula - CH3COOH
what is vinegar used for and in
in household cleaning products as it is non toxic
methanoic , ethanoic and propanoic and butanoic acid are miscible in water this means?
the solubility decreases as size increases
a carboxylic acid increase in size their melting and boiling points increase due to?
the increasing strength of the intermolecular forces
what functional group are carboxylic acids in
carboxyl group - COOH
whta is the general formula for carboxylic acids
CnH2n+1COOH
carboxylic acids can form ….
salts
exothermic
a process that releases heat energy
endothermic
reaction that takes in heat energy
what is combustion
when a substance reacts with oxygen releasing energy
what does hydrocarbons and alchohauls burning with plentiful oxygen produce
CO2 and water
what happens when fuels burn
they release diffrent quantities of energy
