Unit 3. Periodic Table Flashcards
What is the nuclear charge
The number of protons in the nucleus of an atom. Basically the atomic number
Name of vertical columns and horizontal row
Group and period
What does the period number tell you?
The number of occupied main energy levels in an atom
What does the group number tell you?
The number of valence electrons in an atom of that element
Where are metals, non-metals and metalloids located on the periodic table?
Metals located mainly on the left and middle in the s-, f- and d-block.
Non-metal elements are found on the right side in the p-block.
Metalloids (semi-metals) are located in a diagonal staircase that forms a boundary between metals and non metals.
Name the name of the groups in the periodic table and where they are found, as well as their characteristic properties
Alkali Metals- Group 1- most reactive, react strongly with water
Alkaline earth metals- Group 2- reactive but less reactive then group 1
Halogens- Group 17- most reactive group of non-metals
Noble gases- Group 18- very unreactive monatomic gases
Transition metals- D-Block region (apart from zinc)- relatively stable with only moderate reactivity useful for construction
What are the lanthanides and actinides
They are metallic elements that make up the f-block. Their two rows are separated from the rest of the periodic table. Atomic numbers from 89-103, they are radioactive. Lanthanides (57-71) are knows as rare earth metals
What are the s- p- d- and f- block directly correlated to?
The electron configuration with the sub levels: s,p,d,f. The block in which an element is tell us which sub-level is in the process of being filled.
How do you find the v.e of group 13 to 18?
Substract ten from group number.
What is atomic radii
The size of an atom
Trend in atomic radii?
Period
Starting with sodium (11) it decreases across the period until it reaches chlorine (17). Bc we gain an electron and a proton as we go across a period, electron shielding remains more or less constant, as the electrons fill the same main energy level. Therefore there is an increased attraction between the nucleus and outer electrons which pulls them closer.
Group
Going down a group, each element’s v.e occupies another extra main energy level which increases the atomic radii.
What is electron shielding?
Electron shielding occurs when outer electrons are shielded from the attraction of the nucleus by inner electrons knows as shielding electrons.
Which are more likely to become anions and cations, metals or non metals?
Metallic elements tend to loose electrons and form cations.
Non metallic elements tend to gain electrons and form anions
What are isoelectronic species?
Isoelectronic species have the same electron configuration. Example: Na+, Mg2+. They have different numbers of proton but same of electrons.
What is the ionic radius
The distance between the nucleus of an ion and the outermost energy shell of the ion