Chapter 7 Periodicity Flashcards
Periods
A horizontal row of elements in the periodic table. Elements show trend in properties across a period.
Periodicity
A repeating trend in properties of the elements across each period of the periodic table.
Groups
A vertical column in the periodic table. Elements in a group have similar chemical properties and their atoms have the same number of outer shell electrons.
first ionisation energy
The energy required to remove one electron from each atom in one mole of gaseous atoms of an element to form one mole of gaseous 1+ ions.
shielding effect
The repulsion between electrons in different inner shells. Shielding reduces the net attractive force between the positive nucleus on the outer shell electrons.
second ionisation energy
The energy required to remove one electron from each ion in one mole of gaseous 1+ ions of an element to form one mole of gaseous 2+ ions.
metallic bond
The electrostatic attraction between positive metal ions and delocalised electrons.
delocalised electrons
Electrons that are shared between more than two atoms.
giant metallic lattice
A three-dimensional structure of positive ions and delocalised electrons, bonded together by strong metallic bonds.
giant covalent lattice
A three-dimensional structure of atoms, bonded together by strong covalent bonds.
Blocks
Elements can be divided into blocks corresponding to their highest energy sub shell. This gives the S,p,d and f block.
Alkali metals
Li, Na K Rb Cs Fr
Group number 1
Alkaline earth metals
Be Mg Ca Sr Ba Rb
Group 2
Transition elements
Group 3-12
Pcnictogens
N P As Sb Bi Group 15 (5)
