Chemistry - electronic configuration , electrons , ions , ionic substances , bonding ., periodic table - all for exams Flashcards
what order are electrons filled in using SPD ?
1s2 , 2s2 , 2p6 , 3s2 , 3p6 , , 3d10 , 4s2
what order are electrons removed when using SPD ?
1s2 , 2s2 , 2p6 , 3s2, 3p6, 4s2 , 3d10
what are the rules when filling boxes to show electron configuration
- Folow the rule of electron configuration .
- In each box arrows go in opposite directions.
How do you know the charge of a transition metal ion ?
Hydrogen is given in roman numerals
what are the charges of protons , neutrons and electrons ?
Proton = +1
Neutron = 0
Electron = -1
what are the masses of protons , neutrons and electrons
Proton = 1
neutron = 1
Electron = very small
what are the 3 types of bonding and where do they occur
Covalent bonding - non metals only
Metallic bonding - Metal only
ionic bonding - non metals and metals
why do ionic substances have a high melting and boiling point ?
This is because of the strong electrostatic force of attraction holding the opposite charged ions together and a large number of ionic bonds in an ionic lattice.
why do ionic substances don’t conduct electricity when solid ?
Ionic compound cannot conduct electricity when solid as their ions are held in fixed positions and cannot move.
why do ionic substances conduct electricity when molten or liquid ?
Ionic substances conduct electricity when molten or liquid because ions are free to move in the substance.
why do covalent substances have a low melting and boiling point ?
Covalent substances have a low melting and boiling point due to the weak intermolecular substances . Little energy is needed to break the covalent substances.
why do covalent substance do not conduct electricity ?
covalent substances do not conduct electricity because there are no charged particles to move and carry charge. Most covalent compounds are insoluble in water.
why do metallic substances have a high melting and boiling point ?
This is because the increased positive charge on the metal ions and the increased number of electrons that are delocalised . this means stronger bonding
why do metallic substances do conduct electricity ?
Metallic substances conduct electricity because they have free electrons or delocalised electrons
why are metallic substances malleable and ductile ?
They are due to structure of their atoms which allows layers to slide over each other . Metals are made of a positive ion lattice surrounded by a sea of delocalised electrons
what is the meaning of dative / coordinate bonding ?
Dative or coordinate bonding is a shared pair of electrons from the same element.
what is the definition of electronegativity ?
Electronegativity is the tendency of an element to attract a shared pair of electrons towards it in a covalent bond.
where are electronegative elements found ?
Electronegative elements are found on the top right of the periodic table .
what are examples of some electronegative elements in the periodic table ?
Fluorine , Nitrogen , oxygen and chlorine
what are the 3 types of intermolecular forces
London forces ( van der woels )
Permeant dipole dipole forces
Hydrogen bonding
what is the order of strength for intermolecular forces ?
Weakest to strongest :
London forces , permanent dipole forces, hydrogen bonding.
where do London forces occur ?
London forces occur between all molecules and compounds .
why do London forces occurs ?
London forces occur because of a temporary dipole caused by an uneven distribution of electrons.
what is the definition of the word malleable ?
Malleable means the metal can change shape.
what is the definition of the word Ductile ?
Ductile means the metals can stretch into wires.
what is the definition of permanent dipole dipole ?
It is a more electronegative element bonded to a less electronegative causes permanent dipoles
what is the definition of a hydrogen bond ?
This means hydrogen is bonded to either fluorine , nitrogen or oxygen
explanations of hydrogen bonding ( 6 marks )
- oxygen or fluorine is a very electronegative so attracts the bonded pair of electrons in the covalent bond to become a negative charge.
- hydrogen becomes a positive charge.
- The positive charge on the hydrogen is attracted to the unbonded electrons on the oxygen or fluorine.
what is the trend of ionic and atomic radii ?
Across a period you get smaller electrons due to more protons
Down a group the electrons get bigger due to more shells.
what are the two factors that determine the strength of an ionic bond ?
- charge of the ions
- Size of the ions.
what is the definition of atomic number ?
The atomic number is the same number of protons is equal to the same number of electrons
what is the definition of mass number ?
The mass number is the same number of protons and electrons but a different number of neutrons.
How many electrons are in the s orbital
2
How many electrons are in the P orbitals
6
How many electrons are in the d orbitals
10
what do elements in the same group have ?
They have similar physical and chemical properties
what do elements in the same period have ?
They have the same number of electron shells , and similar physical proporties.
what is the definition of an ionic bond ?
An ionic bond are metals that lose electrons and non metals that gain electron by gaining a charge .
what is the definition of the word electrostatic
Electrostatic is a force between postive and negative charges.
what happens to the size of an ion as you go down a group ?
the size of the ion gets bigger because the ions gets more shells.
what is the definition of relative formula mass
Relative formula mass is the sum of relative atomuc masses of the elements present in a formula unit
what is the definition of the word mole ?
The mole is a fundamental unit of measurement that is avogrados constant number.
what is the definition of theoretical mass ?
Theoretical mass is the mass that we have calculated
ways in how does the theoretical mass change ?
- residues left behind in containers
- products turn into a gas . gas evaporates and goes away - evaporation.
- spillages
what is the formula to calculate percentage yield
% percentage yield = Actual mass / theoretical mass x 100
what is the definition of relative atomic mass ?
The relative atomic mass is the weighted average mass that takes into account the abundance of isotopes
what is the formula to calculate relative atomic mass ?
Relative atomic mass = ( mass of an isotope x isotope abundance ) + ( mass of an isotope x Isotope abundance )
what is the definition of an Ion
Ions are atoms that have gained or lost electrons so they have a charge
what do positive ions do ?
positive ions lose electrons.
what do Negative ions do ?
Negative ions gain electrons
what is the formula to calculate moles ?
moles = Mass / relative atomic mass
What is an Atom ?
An atom has a small positively charged nucleus surrounded by orbiting negatively - charged electrons.
what is the structure of an Atom ?
- Atoms are vey small and have a radius of about 1 x 10 metres.
- The electrons are arranged at different distances from the nucleus
- Most of the mass of an atom is concentrated in the nucleus
what has a small positively charged nucleus surrounded by orbiting negatively charged electrons ?
Atom
Where is most of the mass of an atom found ?
The nucleus
Where in an atoms are protons found ?
In the nucleus
In what environment would the relative mass of an atom change ?
Mass is constant across all environments
What is an example of an atomic model ?
Hydrogen atom
What 2 things have the largest mass ?
An atoms
An atoms nucleus
What are electrons arranged in ?
Electrons are arranged in shells.
What is the name of the shell for atoms that have more than one electron ?
Shells are split into sub - shells.
what are orbitals labelled by ?
Letters
what is the word for orbitals that are exactly the same energy ?
Degenerate
What kind of sub shell contains 5 orbitals ?
D
what are the 3 facts about orbitals ?
Orbitals are outside of the nucleus.
Orbitals make up sub - shells.
Orbitals can hold up to two electrons.
what is the definition of ionic bonding ?
Ionic bonding is the electrostatic attraction between ions of opposite charges
Are Ionic bonds stronger or weak than intermolecular forces ?
Much stronger than any type of intermolecular force.
What kind of attraction exists in ionic bonding ?
Electrostatic.
How is sodium fluoride formed using a dot and cross diagram ?
The sodium atom transfers its outer electrons to the fluorine atom , creating Na + and F - ions . Both of these ions have full outer shells.
How is calcium oxide formed ?
The calcium atom transfers its 2 outer electrons to the oxygen atom creating Ca2+ and O2- ions which both have full outer shells
what is the empirical formula of an ionic compound ?
The empirical formula of an ionic compound is the simplest ratio of ions possible.
what are the properties of covalent bonds ?
Multiple bonds can be formed between some atoms .
They contain shared pair of electrons.
They can link together to give large structures.
what molecule contains a dative bond ?
Ammonium ion
what is a description of a covalent bond ?
Shared pair of electrons between two atoms.
what is another name for dative bonds ?
Coordinate bond
Why are metals good electrical conductors ?
Free electrons act as charge carriers
What is the strength of London forces ( van der Waals ) interactions dependant on ?
Number of electrons
which 3 elements could form hydrogen bonds ?
Nitrogen
Oxygen
Fluorine
How many oxygen , nitrogen or fluorine atoms are required in a hydrogen bond ?
2
what is an amu ?
A unit of mass , equal to one twelfth the mass of a carbon - 12 atom.
what is the value of Avogadro’s constant ?
6.02 x10 23
what are the units of concentration ?
Mol dm -3
facts about coefficients in chemical reactions ?
Coefficients are used to balance equations
coefficients are useful in molar calculations
The coefficients represent the ratios of each substance.
What features of a reaction make it more likely to be incomplete ?
The reaction is slow.
The reaction is reversible
what 4 factors reduce percentage yield ?
- incomplete reactions
- chemicals stick to apparatus
- side reactions
- separation difficulties
If we divide the real yield by the theoretical yield and multiply by 100 , what figure do we get ?
Percentage Yield
What is the RAM of chlorine ?
35.5
What is the value of Avogadro’s constant ?
6.02 x 10 23
What units are used for volume in the ideal gas equation ?
Cubic metres
What is the periodic table ?
The periodic table is a table that organises all the elements into groups and periods.
what are the elements arranged in the periodic table ?
The elements are arranged in order of proton number starting with hydrogen as hydrogen has a proton number of 1
What is the definition of period in chemistry ?
A period is a row in the periodic table
What are some examples for elements in the same period ?
Magnesium and sulfur
What is the definition of a group in chemistry ?
A group is a column in the periodic table.
What do elements in the same group have ?
They have the same number of valence electrons.
Where are the P block element in the periodic table ?
P block elements lie on the right hand side of the periodic table.
What is the f block made up of ?
Lanthanides and Actinides.
what is the periodic table arranged at ?
Periods and Groups.
which block would the transition metal tungsten lie in ?
D
What is ionisation ?
Ionisation is the reaction where one electron is removed from an atom.
what are the features of the ionisation equation ?
Electrons - removal of one electron
Ion charges - Increase in charge by + 1
State symbols - All atoms and ions in gaseous phase.
The ionisation of a species involves the removal of how many electrons ?
1
What is the first ionisation energy?
The first ionisation energy is the energy required to remove an electron from every atom in a mole of atomic gas to produce a mole of unipositive gaseous ions
What is the second ionisation energy?
The second ionisation energy is the energy required to remove an electron from every ion in a mole of unipostive gaseous ions to produce a mole of dispositive gaseous ions.
What is the third ionisation energy ?
The third ionisation energy is the energy required to remove an electron from every ion in a mole of dispositive gaseous ions to produce a mole of trispostive gaseous ions.
What is the magnitude of the charge on the ion in the reactants of the nth ionisation equation ?
N - 1
What factors affect ionisation energy ?
Electron distance form nucleus - Greater distance decreases the ionisation energy
Nuclear charge - Great nuclear charge increases the ionisation energy
Shielding - More shielding electrons decreases the ionisation energy.
What is the lowest ionisation energy of sodium ?
First ionisation energy
What is the general trend of successive ionisation energies for sodium ?
An increase
What could decrease the ionisation energy ?
Higher principle quantum number
How does ionisation energy vary within the periodic table ?
Increases across a period
Decreases down a group
what will happens to a group trend in atomic radii ?
The group trend in atomic radii is that the atomic radius will increase down the group.
What happens to ionisation energy across the period in the periodic table ?
The ionisation energy increases across the period.
What is electronegativity ?
Electronegativity is the ability of an atom to attract a pair of electrons
When is a molecule polar
A molecule is polar if there is a charge separation between each side of the molecule.
Where are metals found in the periodic table ?
Metals are found on the left of the periodic table because they have few electrons in their outer shell
what are the properties of metals ?
Metals have high melting and boiling points.
Metals are good conductors of heat and electricity.
Metals are all solid at room temperature.
Where are non - metals found in the periodic table ?
Non - metals are found on the right of the periodic table because they have many electrons in their outer shell.
What are the properties of non metals ?
Non metals have low melting and boiling point
Non metals are often fund as gases
Non metals generally do not conduct heat or electricity
What is the name of elements that are in group 1 of the periodic table ?
Alkali metals
What are the 3 alkali metals ?
Lithium
sodium
potassium
what are the properties of the alkali metal lithium ?
- Lithium is the least reactive of the alkali metals
- Lithium burns with a crimson flame when it react with oxygen
- Lithium float on the surface of water and will release bubbles of hydrogen gas ( effervescent )
what are the properties of the alkali metal sodium ?
Sodium is more reactive than lithium because its outer electron is less strongly attracted to the positively charged nucleus . This is because it is greater distance from the positive charge of the atoms nucleus.
The metal floats on the surface of water which releases enough heat to melt the sodium. The sodium moves quickly across the surface of the water.
Sodium burns with a yellow orange flame when it reacts with oxygen.
What are the properties of the alkali metal potassium ?
Potassium is more reactive than lithium and sodium because its outer electron is least strongly attracted to the nucleus.
The metal floats on the surface of water and similar but more vigorous , the reaction compared with sodium.
Potassium burns with a lilac flame when it reacts with oxygen.
What colour of solution is produced when a metal chloride is dissolved in water ?
Colourless
What is the electronic configuration of lithium , sodium and potassium ?
Lithium - 2,1
Sodium - 2,8,1
potassium - 2,8,8,1
What happens to ionisation energy as you go down group 2 and why ?
Ionisation energy decreases because the outer electrons are further away from the nucleus
