Atomic Structure Flashcards
how many elements are there
118
how are the elements get arranged in groups
according to how many are in the outer most energy level
describe alkali metals
VERY reactive
soft
react with water
react with oxygen
describe transition metals
hard and dense
less reactive
used in catalysts
form coloured compounds
describe the halogens
diatomic elements
all toxic
chlorine used to sterilise swimming pools
describe nobel gases
least reactive
DO NOT REACT AT ALL
what is the centre of the atom called and what does it contain what’s its charge
its called the nucleus and contains protons and neutrons and is positively charged
what circles round the atom and what is its charge
the electrons circle round and are negatively charged
how is the atom neutral
its neutral because the number of positively charged protons cancels out the negatively charged electrons
what is the top number mean in nuclide notation
the top number is the mass number
what is the bottom number in nuclide notation and what does it represent
its the atomic number and represents the number of protons and electrons
what are isotopes
isotopes are atoms of the same element have the same atomic number but diffrent mass numbers
how do you calculate the relative atomic mass
(mass of isotopes 1 x %) + (mass isotopes 2 x %) divide by 100
what is the electron arrangement for sodium
2,8,1
why do elements in a group have similar chemical properties
because they have the same number of outer electrons
what is an ion
an ion is where an atom gains or loses electrons and charged particles which are ions are formed
what happens if an atom gains an electron
it becomes a negatively charged ion
what happens if an atom loses an electron
it becomes a positively charged ion.
do metals gain or lose electrons
do non-metals gain or lose electrons
metals always lose to become positively charged
non-metals always gain to become negativly charged
why do atoms lose or gain electrons
its so they achieve a full outer most energy level.
what are atoms joined by
atoms can be joined by bonds
if the bonded atoms are the same what is it
its a molecule of an element
what is a diatomic molecule
diatomic molecules are made up of only two atoms
what are the seven diatomic elements
Oxygen
Flurine
Chlorine
Nitrogen
Hydrogen
Iodine
Bromine
why do atoms form bonds
in order to achieve a most stable outer electron arrangement (a full outer shell)
what is a covalent bond
two positive nuclei held together by their common attraction for the shared pair of negative electrons
what are covalent bonds formed from
they are usually formed between two non-metal elements
are covalent bonds strong
they are extremely strong and need lots of energy to break
what are bonding diagrams
they are simplified pictures of an atoms outer electrons
how do atoms form bonds
using the electrons in their outer most energy level
what molecular would hydrogen oxide be
angular
what are covalent networks
gains network structures held together by strong covalent binds
give an example of chemical formula
H2O
what is the formula to work out the valency
Symbol
Valency
Swap
Divide
Formula
what would be the valency for Magnesium chloride
Mg Cl
2 1
1 2
1 2
MgCl2
what are the Roman numerals from 1-7
1 - I
2 - II
3 - III
4 - IV
5 - V
6 - VI
7 - VII
what is the valency for iron(II)chloride
S - Fe Cl
V - 2 1
S - 1 1
D - 1 1
F - FeCl2
what are the prefixes for numbers 1-7
1 - mono
2 - di
3 - tri
4 - tetra
5 - penta
6 - hexa
7 - heat
what would thee answer be t o carbon monoxide
CO
when does ionic bonding occur
between a metal and non-metal
between an positive and negative ion
what is an ionic lattice
a giant arrangement of ions held together by electrostatic attraction (ionic bonds)
what are 3 things you know about ionic lattice
it consists of millions of ions held together by ionic bonds
lots of energy required to break the bonds
always solid at room temputure
what is the ionic formula for Hydrogen fluride
S - H. F
V - 1. 1
S - 1. 1
D - 1. 1
F - HF
I - H+F-
what are the charges on the ions for numbers 1-7
1 - +
2 - 2+
3 - 3+
4 - /
5 - (-)
6 - 2-
7 - 3-
what is a conductor of electricity
it allows electric current to flow through
what is a non-conductor of electricity
it does not allow electrical current to flow through
are metals elements conductor or not
they do conduct
do non-metals conduct
NO
what is metallic bonding
the outer electrons of metal atoms are not attached to a particular atom and are free to move around. THEY ARE DELOCALISED
why do metals conduct electricity
because electrons can flow through them
what is covalent bonding
where electrons are not free to ,one around and there is no conduction of electricity
what is conductivity in non-metals
non-metals do not have charged particles which can move therefore they do not conduct electricity
do covalent compounds (solid, liquid, gas) conduct electricity
NO
because they are not free to move around
do ionic compounds electricity at all
yes when dissolved in water or when molten
what happens when melting ionic compounds
it breaks down the lattice and allows the ions to move.
