The Periodic Table Chapter Notes | Chemistry for GCSE/IGCSE - Year 11 PDF Download

 Page 1


Periodic table
? The columns are groups and the rows are periods
? Mass no.
? ? Nucleon no.  number of protons and neutrons
? The no. of protons and neutrons present in the nucleus of an atom
? Atomic no.
? No. of protons
? The no. of protons present in the nucleus of an atom
? Valency of an element is the number of electrons its atoms lose or gain to form a compound
? Upto = 2n^2
? ? ? Columns  groups  no. of electrons in outer shell
? ? ? Rows  periods  gives you the no. of shells present in the atom
Group 1 (Alkali metals)
? Group 1 metals have 1 electron in outermost shell
? The relative molecular mass increases down the group
? Trends
? Mp/Bp decreases down the group
? Density increases down the group
? Reactivity increases down the group
? Becomes softer down the group
? The alkali metals react vigorously with water giving out hydrogen bubbles, leaving solutions of
their hydroxides which are alkalis
? Alkali metals when reacted with chlorine burst into flames, they burn brightly, forming chlorides
? Alkali metals burst into flames when you heat them and put it in a jar of oxygen, they burn
fiercely to form oxides
? Atoms with the same number of valence electrons react in a similar way
? The alkali metals are the most reactive of all metals as they need to lose only one electron to gain
a stable outer shell
? The alkali metals form ionic compounds, in which the metal ion has a charge of 1+. The compounds
are white solids. They dissolve in water to give colourless solutions
Page 2


Periodic table
? The columns are groups and the rows are periods
? Mass no.
? ? Nucleon no.  number of protons and neutrons
? The no. of protons and neutrons present in the nucleus of an atom
? Atomic no.
? No. of protons
? The no. of protons present in the nucleus of an atom
? Valency of an element is the number of electrons its atoms lose or gain to form a compound
? Upto = 2n^2
? ? ? Columns  groups  no. of electrons in outer shell
? ? ? Rows  periods  gives you the no. of shells present in the atom
Group 1 (Alkali metals)
? Group 1 metals have 1 electron in outermost shell
? The relative molecular mass increases down the group
? Trends
? Mp/Bp decreases down the group
? Density increases down the group
? Reactivity increases down the group
? Becomes softer down the group
? The alkali metals react vigorously with water giving out hydrogen bubbles, leaving solutions of
their hydroxides which are alkalis
? Alkali metals when reacted with chlorine burst into flames, they burn brightly, forming chlorides
? Alkali metals burst into flames when you heat them and put it in a jar of oxygen, they burn
fiercely to form oxides
? Atoms with the same number of valence electrons react in a similar way
? The alkali metals are the most reactive of all metals as they need to lose only one electron to gain
a stable outer shell
? The alkali metals form ionic compounds, in which the metal ion has a charge of 1+. The compounds
are white solids. They dissolve in water to give colourless solutions
Group 2 (Alkaline Earth metal)
? They react with oxygen to form metallic oxides and react with water to form hydrocarbons
? Valency = +2
? Outer Shell = 2
? Trends
? Melting point decreases down the group
? Density increases down the group
? Reactivity increases down the group
? Uses
? Calcium used in body for bones and teeth
? Beryllium is used to make jewelry and emeralds
? Magnesium is used to make medicines
Group 7 (Halogens)
? Outer shell = 7
? Valency = -1
? Trends
? Colour gets deeper down the group
? Density increases down the group
? Boiling point increases down the group
? Reactivity decreases down the group
? Halogens react with metals to form compounds called halides
? A halogen will displace a less reactive halogen from a solution of its halide
Group 8 (Noble gases)
? Group 8 either has 2 or 8 electrons in their outermost shell that allows them to be stable
? Properties
? Non-metals
? Colourless gases
? Monatomic gases
? Unreactive because their atoms already have stable outer shells
? Trends
? The atoms increase in size and mass down the group
? Density of gases increases down the group
? B.P increases down the group
? Uses
? ? Helium  balloon, airships
? ? Argon  tungsten bulbs
? ? Neon  Glows red
Page 3


Periodic table
? The columns are groups and the rows are periods
? Mass no.
? ? Nucleon no.  number of protons and neutrons
? The no. of protons and neutrons present in the nucleus of an atom
? Atomic no.
? No. of protons
? The no. of protons present in the nucleus of an atom
? Valency of an element is the number of electrons its atoms lose or gain to form a compound
? Upto = 2n^2
? ? ? Columns  groups  no. of electrons in outer shell
? ? ? Rows  periods  gives you the no. of shells present in the atom
Group 1 (Alkali metals)
? Group 1 metals have 1 electron in outermost shell
? The relative molecular mass increases down the group
? Trends
? Mp/Bp decreases down the group
? Density increases down the group
? Reactivity increases down the group
? Becomes softer down the group
? The alkali metals react vigorously with water giving out hydrogen bubbles, leaving solutions of
their hydroxides which are alkalis
? Alkali metals when reacted with chlorine burst into flames, they burn brightly, forming chlorides
? Alkali metals burst into flames when you heat them and put it in a jar of oxygen, they burn
fiercely to form oxides
? Atoms with the same number of valence electrons react in a similar way
? The alkali metals are the most reactive of all metals as they need to lose only one electron to gain
a stable outer shell
? The alkali metals form ionic compounds, in which the metal ion has a charge of 1+. The compounds
are white solids. They dissolve in water to give colourless solutions
Group 2 (Alkaline Earth metal)
? They react with oxygen to form metallic oxides and react with water to form hydrocarbons
? Valency = +2
? Outer Shell = 2
? Trends
? Melting point decreases down the group
? Density increases down the group
? Reactivity increases down the group
? Uses
? Calcium used in body for bones and teeth
? Beryllium is used to make jewelry and emeralds
? Magnesium is used to make medicines
Group 7 (Halogens)
? Outer shell = 7
? Valency = -1
? Trends
? Colour gets deeper down the group
? Density increases down the group
? Boiling point increases down the group
? Reactivity decreases down the group
? Halogens react with metals to form compounds called halides
? A halogen will displace a less reactive halogen from a solution of its halide
Group 8 (Noble gases)
? Group 8 either has 2 or 8 electrons in their outermost shell that allows them to be stable
? Properties
? Non-metals
? Colourless gases
? Monatomic gases
? Unreactive because their atoms already have stable outer shells
? Trends
? The atoms increase in size and mass down the group
? Density of gases increases down the group
? B.P increases down the group
? Uses
? ? Helium  balloon, airships
? ? Argon  tungsten bulbs
? ? Neon  Glows red
? ? Krypton  lasers
Transition metals
? Properties
? Hard, tough and strong
? High m.p
? Malleable and ductile
? Good conductors of electricity and heat
? High density
? Chemical properties
? They are much less reactive than Group 1 metals
? They show no clear trend in reactivity
? Most transition elements form coloured compounds
? Most can form ions with different charges
? They can form more than one compound with another element
? Transmission elements have variable oxidation states
? Most transmission elements can form complex ions
? Uses
? Used in structure like bridges and buildings in form of steel (alloy)
? Help in making alloys
? Used as conductors of heat and electricity
? Many transition elements and their compounds act as catalysts