Structure and Bonding Flashcards
Understand all types of atom's bonds and structure
How many electrons can an s subshell hold?
2
How many electrons can a p subshell hold?
6
How many electrons can a d subshell hold?
10
How many electrons can a f subshell hold?
14
What is Aufbau principle?
Electrons always inhabit the lowest energy orbitals available
Electrons repel each other so what holds them together and why?
Spin creates magnetism (moving charge)
Opposite spin creates opposite magnetic fields
What is does electronegativity mean?
How attractive a nucleus is to electrons
What are the properties that affect electronegativity?
Larger charge=more attractive
Charge density, more neutrons “dilute” positive charge =lower attractive
Inner electrons shield outer electrons reduces attraction
Distance, the further away, the weaker the attraction
What is the most electronegativity element
Fluorine
Why does ionic bonding occur?
Because the non-lethal has higher electronegativity so it steals electrons from the metal
Why does convent bonds occur?
Similar electronegativity so they share electrons instead of stealing
Why does metallic bonding occur?
Same electronegativity so they share electrons between the positive nucleuses
Delocialised electrons
What happens to electronegativity across periods?
Adds protons so it increases
What happens to electronegativity down groups?
More distance and more shielding so decreasing electronegativity
What is stoichiometry?
The ratios of reactants
What is promotion and why is it important?
Promotion is when electrons from 2s^2 move to 2p orbit
Promotion explains how carbon bond makes colavent bonds as it means a sub shell is freed up for an electron to bond
A mixture of s, p electrons forming a bond
Ionic electron clouds look like
Cloud is more around the highly electronegative atom because more attractive to electrons
One side is denuded of electrons
Colavent electron clouds look like
Even spread as similar electronegativities
What are the 3 types of Van der Waals forces
Hydrogen bonding
London dispersion forces (temporary dipoles)
Permanent dipoles
What are Van Der Waals forces
Weak attractive forces between molecules
What is a tetrahedron and what angle between pairs?
The shape a molecule forms with one central atom and 4 bonded atoms
109.47°
How do London dispersion forces work?
Electrons repel each other to create temporary positive charge in the charge cloud
The charged bits are then attracted to each other
What is the order of strength of Van Der Waals forces?
Hydrogen
Permanent dipoles
London dispersion forces
How do you work out moles?
Moles = Mr/Mass
What order do the orbital go in?
S, p, d, f
How do you calculate molar mass?
Mass/moles
How do you calculate concentration?
Moles/volume
What are the uses for magnesium oxide?
Fertilizer Mineral supplement Ice control Dust control Coagulant for making food Spa treatment
Explain why copper is ductile?
Metallic bonding means a regular pattern
This means atoms can slip past each other easily
So metals can be drawn into wires without breaking
Balance equation for the reaction of silicon and oxygen
Si + O^2 –⟩ SiO^2
What is the force called between ions?
Electrostatic force
What is the formulae of hydroxide?
OH-
What is the formulae of carbonate
CO3²-
small low 3
What is the formulae of sulphate
SO4²-
small low 4
small high 2
What is the formulae of nitrate
NO3-
small low 3
What is the formulae of ammonium
NH4+
small low 4
How do you work out molarity?
Molarity= moles/ litres of solution
What is Aufbau principle?
Electrons will fill the orbital with the lowest available energy state
What intermolecular forces do noble gases have?
London dispersion forces
How do you work out percentage yield with moles?
Actual number of moles/expected number of moles *100
What is an element?
A substance made from one type of atom
What is a quantum?
A quantum is how much energy an electron needs to move to the next energy level
Losing energy is dropping a level
Gaining energy is moving up a level
What’s important to remember when drawing calcium electron configuration which has 20 electrons?
4s fills in before 3d
What is the structure of ionic compounds?
Lattice giant structure usually regular pattern
What does the strength of an ionic bond depend on?
More charge means more electrostatic forces
Smaller ionic radius electrons are closer to the nucleus
What is a dative bond?
Where the electrons come from the same atom, Colavent bond
What affects the strength of covalent bonds
Shorter covalent bonds on a stronger closer to the nucleus
Multiple bonds are stronger
Why are metals good conductors of heat?
At higher temperatures metal atoms vibrate more. Bypass this vibration energy (kinetic/heat) to their neighbours
Free electrons carry energy through the metals
Why are metals good conductors of electricity?
Electrons are delocalized and negatively charged
Free electrons can move through the metal and current is the flow of charge
Why does the melting point decrease as we go down metals groups?
The atoms of bigger as they have more shells
The distance between the nucleus and the delocalized electrons are bigger
The forces holding the structure together are weaker
What are inter-molecular forces and their name?
The forces between molecules
Van de Waals forces
Why are elements put into groups?
Put into groups of similar properties
How many elements is there?
92
What is electron affinity and what is it measured in?
How likely a neutral atom is to gain an electron
Measured in the energy released Kj/mol
