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Periodic table - Coggle Diagram
Periodic table
noble gases (Group 18)
monoatomic
unreactive
atoms react in order to gain a stable outer shell of electrons. But the atoms of the noble gases already have a stable outer shell with 8 electrons, except for helium which has 2 (since it has only one shell)
So the atoms have no need to react in order to gain or lose electrons. Because already have a stable outer electron shell.
Physical propreties
gases grow denser down the group, because the mass of the atoms increases.
The increase in boiling points is a sign of increasing attraction between atoms. It gets harder to separate them to form a gas.
Uses
Helium is used to fill balloons and airships, because it is much lighter than air
Argon is used to provide an inert atmosphere.
-as a filler in tungsten light bulbs.
-to protect metals that are being welded. It won’t react with the hot metals
Neon is used in advertising signs.
Krypton is used in lasers – for example for eye surgery
It is used in lighthouse lamps, lights for hospital operating rooms, and car headlamps
Group 1 (alkali metals)
melting point / boiling point
decreases down the group, because ions get larger the distance between the bonding electrons
reactivity
increases reactivity down the group. It is easier for G1 metals to donate electrons, the valence electron is further away from the nucleus. If it easier to give away, means its more reactivity
ionisation energy
decreases down the group, because there is more shielding between the nucleus and the outer electrons
Group 17(Halogens)
boiling point /melting point
it decreases down the group, because the size of molecules increase down the group. G17 elements usually accept electrons.
reactivity
decreases down the group, because the electrons in the outer shell move further away from the nucleus as we go down the group.
ionisation energy
decreases down the group, because
Transition metals (Group 3-12)
Physical Properties
hard, tough and strong
high melting points and high density
Iron- 7.9 g/cm3, MP 1535 °C
copper- 8.9 g/cm3, 1083°C
nickel-8.9 g/cm3, 1455°C
malleable (can be hammered into different shapes) and
ductile (can be drawn out into wires).
good conductors of heat and electricity. Of all the metals, silver is
the best conductor of electricity, and copper is next.
Chemical properties
are much less reactive than the Group I metals. EX: copper and nickel do not react with water, or catch fire in air. Unlike sodium. In general, the transition elements do not corrode readily in the atmosphere.
show no clear trend in reactivity, unlike the Group I metals.
Most transition elements form coloured compounds.
Most can form ions with different charges. EX:copper: Cu +,Cu 2+
iron: Fe 2+, Fe 3+
They can form more than one compound with another element. copper(I) oxide, Cu2O copper(II) oxide, CuO
iron(II) oxide, FeO iron(III) oxide, Fe2O3
The Roman numeral in brackets tells you how many electrons the
metal atom has lost. This number is called its oxidation state.
Uses
The hard, strong transition elements are used in structures such as bridges, buildings, and cars. Iron is the most widely used – usually in the form of alloys called steels.
Many transition elements are used in making alloys. For example,
chromium and nickel are mixed with iron to make stainless steel.
Transition elements are used as conductors of heat and electricity. For example, steel is used for radiators, and copper for electric wiring.
Many transition elements and their compounds acts as catalysts. For example, iron is used as a catalyst in making ammonia
Metalloids
Boron, Silicon, Arsenic, Carbon, Germanium
Periodic trends
Across periods
outer-shell electrons increases by 1 each time.
It is the same as the group number, for Groups I to VII.
Melting and boiling points rise to the middle of the period, then fall to very low values on the right. (Only chlorine and argon are gases at room temperature.)
the atomic radius decreases, that is, the atom is smaller. The outer electrons are closer to the nucleus and more strongly attracted to the center. Therefore, it becomes more difficult to remove the outermost electron.
reactivity increases as you go from the left to the right across a period.
Electronegativity increases, Towards the left of the table, valence shells are less than half full, it requires less energy to lose an electron than to gain one and have low electronegativity.