Ch 5 Flashcards
What is the periodic law?
States that the properties of elements recur in a repeating pattern when arranged according to INCREASING ATOMIC NUMBER
What is a noble gas?
Inert gasses in row 18 of periodic table that show no chemical reactions.
What is a group?
A vertical column in the periodic table.
A.k.a: family
What is a period?
A horizontal row in the periodic table.
A.k.a: Series
What are alkali metals?
Family of group 1a/1
What are alkaline earth metals?
Elements in group 2a
What are halogens?
Elements of group 17a
What are representative elements?
Found in the a groups, on left and rights sides of periodic table.
• have predictable behaviors
What are transition elements?
Found in b groups in middle of periodic table.
•reactions un-predictable
What are inner transition elements?
Beneath main portion of the periodic table.
What is the lanthanide series?
La-Iu series on periodic table
What are rare elements?
Elements #21,39,57,58-71
What is the actinide series?
Elements Ac- Lr
•part of period 7
•all are radioactive
What are transuranium elements?
The elements with atomic numbers beyond 92.
• all elements following uranium are synthetic
Definition of atomic radius?
The distance from the nucleus to the outermost electrons.
•represented in nanometers
What is the trend if the atomic radius?
Atomic radius decreases up a group
• Atomic radius decreases across a period from left to right
What is the trend if metallic characteristics?
As we move left to right metallic characteristic decreases across a period
• metallic characteristics decrease up a group
What is the rule for predicting chemical properties
Elements in the same groups react in similar fashions
Ex: MgO and CaO react the same
Describe the pattern of sub-levels of the blocks in the periodic table
1s2,2s2,2p6,3s2,3p6, 4s2, 3d10, 4p6, 5s2, 4d10, 5p6… So on
Describe the shorthand for electron configuration.
The preceding noble gas is placed in brackets , followed by the outermost electrons and sublevels
Ex: [Ne] S3^1 = Na
Define valence electrons
The outermost electrons that form chemical bonds between atoms and are responsible for the chemical behavior of the element.
•The number of valence electrons is total to number of electrons in the outermost s and p sub-levels
. Can also predict by noting the group number (ex. Group 13-3, group 1-1)
Describe how to use the electron dot formula.
1• write the symbol of the element to represent its core electrons ( inner electrons, ones not bonding)
2• draw each valence electron determines by the element on the periodic table (1 dot per valence electrons)
3• max of 2 dots on each side, max of 8 total
What looses electrons more easily, metals or nonmetals?
Metals
Metals become positively charged after losing an ….
Electron
