Chem Unit Test (Oct. 7) Flashcards
(24 cards)
What did Dobreneier do
Made Triads (groups in periodic table of 3)
Newlands
arranged elements in groups of 8
Mendeleev
Credited with the modern periodic table shape, arranged his table in order of increasing atomic mass.
rutherford
figured out the structure of atoms
Moseley
Discovered the unique atomic numbers
What is an Isotope?
An atom that has gained or lost neutrons, changing the mass but not the atomic number
Order of periodic table columns
Alkali Metals, Alkaline Earth, Metals, Metalloids, Non metals, Halogens, noble gases
What do all the elements in the same horizontal row have in common?
same # of orbits
What do all the same elements in same group have in common
same # of valence electrons; their ions have the same charges
Atomic Radius
The estimated size of an element from the nucleus to the outer perimeter
Atomic radius …… As you move left to right and why
Gets smaller; add more protons and electrons, making the attraction stronger and pulling shells closer
Ionization energy Definition
the energy needed to remove an electron from a gaseous atom
Ionization energy ___ as you go left to right on the periodic table and why
Increases (because you need more energy bc shells are so close together) Ionization energy gets weaker as you move down a family
Multiple Ionization energy (Describe)
Taking of more than 1 electron from a gaseous atom ; It gets harder to take more and more electrons from an atoms because protons pull harder when losing electrons
Electron Affinity
energy released when an electron is ADDED to a gaseous atom
Electronegativity
the strength of attraction an atom has for electrons while in a chemical bond
Elecronegativity __ as you go left to right
Increases because there’s more protons to attract electrons
Electronegativity ___ as you go down a column (family)
Decreases because theres more orbits
Electronegativity’s role in types of Bond
More electronegative elements have the tendency to form higher ionic character bonds with other elements
Ionic Compounds
(Non metal takes electrons from metals)
Covalent Bonds:
Two bullies (Non metals) share electrons
Polar Covalent bonds
two non metals sharing in an unequal way because one is stronger than the other
What is an ion and how are they formed
an ion is a charged atom and they are formed when electrons are removed or added to an element.
Octet Rule
Elements want a full valence shell with 8 electrons
