Module 3: Periodic Table And Energy Flashcards
What is the periodic table arranged by?
Increasing atomic numbers.
What does a ‘Group’ on the periodic table represent?
Colums, the number of electrons in the outer shell of an element.
What does a ‘Period’ on the periodic table represent
Rows, number of electron shells
As you move across a period what is the trend in Atomic Radius and why?
Atomic radius decreases, as the number of protons increase so does the positive charge in the nucleus, further attracting the electrons inwards.
What is ‘Ionisation Energy?’
The energy needed to form cations
What is ‘first ionisation energy?’
The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions.
Example of First Ionisation Energy Equation:
Give the equation for the first ionisation of Hydrogen.
H(g) -> H+(g) + e-
What is the ‘Second Ionisation Energy?’
The energy required to remove one electron from each ion within one mole gaseous, +1 ions to make one mole of gaseous +2 ions.
Example of Second Ionisation Energy Equation:
Give the equation for the second ionisation of Helium.
He+1 (g) —> He+2 (g) + e-
What are the three factors effecting Ionisation Energy and why do these have an effect?
- Atomic Radius: The larger the distance between the nucleus and the outer electron, the less attraction there will be.
- Electron Shielding/Repulsion: Inner shells of electrons repel outer shell electrons as they are all negatively charged, reducing the attraction.
- Nuclear Charge: The lower the nuclear charge, the lower the attractive force on outer electrons.
How can you figure of what element is being represented in a ‘Successive ionisation energies’ graph?
Between shells of electrons, there will be a large increase in ionisation energies; providing evidence for the number shells and the number of electrons in each shell.
What is the Trend in Ionisation Energy across a period and why?
Ionisation Energy increases across a period as the nuclear charge increases, shielding stays the same and atomic radius decreases.
What is the trend in Ionisation Energy down a group and why?
Ionisation Energy decreases, as the atomic radius increases, more electron shielding and nuclear charge decreases.
What is ‘Metallic Bonding?’
The electrostatic attraction between Metal cations and delocalised electrons.
What is a ‘Cation?’
A positive ion
(Cat-ions are paw-sitive… no? okay.)
What is an Anion?
A negatively charged ion.
Describe the structure in a Giant Metallic Lattice.
A pool of delocalised electrons in a giant lattice of regularly arranged positive ions.
What are the properties of Giant Metallic Lattices? (hints: m.p. b.p., e, m, d)
- High melting and boiling points: Strong electrostatic attraction requires lots of energy to overcome.
- Conducts electricity: as electrons can freely move around, carrying electrical charges.
- Ductile (can be stretched) and Malleable (shaped): as ions can slide over each other.
What are the properties of Diamond Giant Covalent Structures?
- Each carbon makes 4 bonds.
- Hard lattice structure.
- Does not conduct as there are no free, outer electrons (all in covalent bonds.)
What are the properties of Graphite Giant Covalent Structures?
- Each carbon makes three bonds.
- Soft (as layers can slide over each other)
- Can conduct (free electron not involved in bonding carries charge.)
What are Diamond Giant Covalent Structures and Graphite Giant Covalent Structures made from?
Pure carbon
What’s 9 + 10?
21
What are the names of Group 0, 1 & 7 elements?
0: Nobel Gasses
1: Alkali Metals
17: Halogens
What is the trend in reactivity in group 2?
Reactivity increases moving down the group.
What is one use of Mg(OH)2 ?
Used to neutralise stomach acid, producing salt and water.
What is one use of Ca(OH)2 ?
Used to neutralise acidic soils.
What is one use of calcium carbonate (CaCO3) ?
Building and construction uses (present in limestone and marble).
Does melting and boiling points increase or decrease down group 17 and why?
Increase, as an increase in electrons increases intermolecular forces.
What happens during a Displacement Reaction?
A more reactive element takes the place of a less reactive element in a compound.
Does reactivity increase or decrease down group 17?
Decreases as atomic radius increases and electron shielding increases.
What is Reduction and what is Oxidation?
Reduction is the gain of electrons during a reaction, Oxidation is the loss of electrons.
What is a Disproportionation Reaction?
A reaction in which an element is both oxidised and reduced?
Describe the method and possible results for the test for Halide Ions.
Add an aqueous solution of silver nitrate to a Halide Solution and note the colour of the precipitate formed.
White precipitate indicates Silver Chloride formed.
Cream precipitate indicated Silver Bromide formed.
Yellow Precipitate indicates Silver Iodide formed.
