Foundations in Chemistry (Module 2) Summary Notes A-level Chemistry
Periodic Table and Energy Change (Module 3) Summary Notes A-level Chemistry
OCS AS LEVEL CHEMISTRY A 2023 VERSION 2 DEPTH IN CHEMISTRY GRADED A+ GUARANTEED PAS
All for this textbook (84)
Written for
A/AS Level
OCR
Chemistry A
AS Unit F322 - Chains, Energy and Resources
All documents for this subject (13)
Seller
Follow
teokosev0
Content preview
PERIODIC TABLE
AND ENERGY
The Periodic Table
Groups, Periods and Blocks
The periodic table a l l te
hle
e m e n ts by proton from lowest to
arranges
number
highest.
·
Periods
↳ A in the
r ow
periodic table.
↳All elements
t h e i r valence electron in the
with same shell
go
in the same
period.
·
Groups
↳ A in the
c olumn periodic table.
↳Elements in the
group have
same their electrons in similar orbitals
↳ Often have similar properties.
↳Have the same amount of electrons in their o u te r shell.
·
Blocks
↳ The two most left columns make block.
the
up
↳ All the elements in this block have their valence electrons in sorbitals.
Helium
↳
is too in this block.
↳ The the p block.
six
rightmostcolumns make up
↳ All the elements in this block have
partially filled
a
p sub-shell.
↳ d Block lies betweenthe sand
p block.
↳Elements in a block a sub-shell.
have
partially filled
a
↳ The f block is detached
along t h e bottom of the
periodic table.
↳ Elements f block have filled of sub-shell.
in the a
partially
Ionisation Energy
Ionisation energy is the
energy required
to re m ove one mole of
e lectrons
from mole of ions.
one
gaseous atoms or
Xigter) standtesterent
First Ionisation
Energy: Xig -> Xg+e-
Second Ionisation
Energy: Xyl-Xg+e= &
Third Ionisation Energy. Xig
->
,Factors Affecting
Ionisation Energy
·
Distance from t h e nucleus
↳Electrostatic attraction decreases the further electrons a re from nucleus.
↳ Less
energy is needed to re m ove electrons which a re further
away.
↳Therefore as distance increases, ionisation decreases.
energy
Nuclear
charge
·
↳ The the number of
greater protons in the nucleus, the
greater the attraction
of the electrons the
to nucleus.
↳ More is needed remove the electron.
energy
to
↳
Therefore, ionisation
energy is
greater.
·
Shielding
↳The the number of
e lec trons between the
greater nucleus and outer
the electrons,
the lower the effectiveness of
nuclear
charge.
↳Positive electrons
charge that
gets elec trons is
to reduced bythe in between.
↳The the number of ionisation
greater electrons, the lower the
energy.
Ionisation Energy Graph of Sodium
·
The graph shows the trend i n successive
ionisation of sodium. This evidence
energies
for the structure of an atom.
·
Ionisation energy increases with proximityto
the nucleus.
↳
The ionisation
1
n= shell will have a
higher
than the 2 shell.
energy n
=
↳ The 2
n= shell will have a
higher ionisation
energy than the n 3 shell
=
Trends in Ionisation
·
Down a
group
First
↳
ionisation energies decrease.
↳
This is because the atomic radius increases.
↳
Electron is further away from nucleus so
experiences less attraction.
↳ There a re also m o re electrons between the nucleus and the outer electrons.
↳ Outer electrons experience m o re
shielding therefore do not
getthe full attraction.
Across
·
a
period
↳First
ionisation
energy increases.
↳ Atomic radius decreases. Proton number increases electrons a re attracted
across a
period so m o re
to the nucleus.
↳ The electron is closer t h e nucleus attraction.
to so
experiences greater
Nuclear
↳
charge increases across a
period.
, Metallic Bonding and Structure
Metals bond in a different way
to non-metals.
·
Seaoffree electrons
↳ In a metal, the valence electrons delocolise, an d can m ove around the
entire metal.
↳ Metalic sec off ree electrons
bonding is viewed as a
surrounding positive
you cores.
↳The
positive ion core s a re attracted to the free electrons.
·
Electrical conductivity
↳Metals a re
good
electrical conductors because the free electrons can
m ove a n d cur rent.
carry
↳
They a re called
charge car riers.
Melting
·
point
↳Related to the
groupof
the metocl.
↳
Ag roup
2 metal will donate two electrons to the sea of electrons.
↳Positive ion
charge.
h e re 2+
c o re s
carry a
↳
The 2+ ion
stronger attraction to the free electrons.
has a
Melting point is higher.
↳
↳
E.g. Sodium melts a t 98°, Magnesium melts a t 650°C.
Structure ofSolid State Metorls
Metals in a solid state can be defined
by atoms
arranged in rows and held
together through
the principles of metallic
bonding.
·
Metolic lattices
↳ All metals, when solid, their
display atoms in a
giant metallic lattice.
↳Atoms a re
arranged in
regular rows, held in place through electrostatic attraction
between the positive metal ions and their delocolised electrons.
↳ Rows s
able t ol i d e ove r each to bend and be
a re
other, giving metals the ability
beaten into shape (malleable).
Melting and
boiling points
·
↳Metals have a
high level ofa ttrac tion between the metal ions and the electrons.
↳ This they
means, require a lot of
energy
to be
separated and therefore
high melting
and
boiling points.
↳Metals with delocolised electrons tend
m o re to have
higher melting and
boiling points.
·
Electrical conductivity
↳Metals a re
good
electrical conductors because the free electrons can
m ove a n d cur rent.
carry
↳
They a re called
charge car riers.
Strength ofattraction
·
↳ There is the
a
strong attraction between positive metallions and
negative electrons.
↳The easily.
strength of these attractions means metals do not dissolve
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller teokosev0. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $3.86. You're not tied to anything after your purchase.