Bonding Test Flashcards
what is chemical bonding?
how atoms come together
Why do atoms bond
-they bond to become stable (most stable when their s and p orbitals of their outer level are full)
-this is called a full octet because it puts 8 in the outer energy level (octet rule)
Ionic bond
-electrons are transferred
-formed between a metal and an nm
-smallest units are called formula unit
- cation (looses and e) anion (gains e)
-bond is a mutual attraction between a cation and an anion
Monatomic Ions
-ion made of one atom that has lost or gained e’s
How to name cations
To name a cation (positive), name the element.
sodium atom (Na) —> sodium ion (Na1+)
How to name an anion
To name an anion (negative), replace the ending of the element with -ide and then say ion after
Covalent Bonds
electrons are shared
- The smallest unit is a molecule
-formed between 2 or more non-metals or semimetals
-made by sharing valence e-‘s
-the nucleus of one atom attracts the electron cloud of another atom
What happens when covalent bonds dissolve
breaks into molecules
What happens when ionic bonds dissolve
breaks into atoms
Diatomic Molecule (list of them)
HINClBrOF
-two atoms of the same element that are covalently bonded
Ionic v.s. Covalent properties (ionic)
-ionic compounds are usually solids and have high melting points and boiling points.
(why?) when melting or dissolving ionic compounds, you are breaking the ionic bond (electrostatic forces).
Ionic v.s Covalent properties (covalent)
-are usually liquids and gasses and have lower melting and boiling points
(why?) when melting or dissolving molecular compounds, you are separating individual molecules, not breaking molecular bonds.
what kind of bond will it make
bonding is not purely ionic
-the difference in electronegativity determines the nature of a bond
large difference in electronegativity
will form an ionic bond
small difference in electronegativity
polar covalent bond
no difference in electronegativity
non-polar or purely covalent bond
The general rule of bonding
metal+nonmental=ionic
nonmetal+nonmetal=polar cov.
2 same nonmetal non-polar cov.
Polar molecules
the molecule in which electrons are unequally distributed
Metallic Bonding
-within a metal there a no molecules
-metals are bound in crystal structure where every atom is surrounded by the same atoms
-Electrons are delocalized: free to move around the metal. This is called a “sea of electrons”
sea of electrons properties
electrical and heat conductivity
malleability
ductility
luster (shininess)
Electron Dot Figure
-Only valence electrons are shown
-Dots placed around the element’s symbol
-Cannot have more than 8 dots
Double Bond
sharing 2 electron pairs
Triple bond
sharing 3 electron pairs
what is the bond length
it is the distance between 2 bonded atoms at their minimum potential energy
-the average distance between the nuclei of two atoms that are chemically bonded together in a molecule
ionic v.s covalent bond length
in general, ionic bonds are stronger and therefore have a shorter bond length than covalent bonds.
bond length (order)
single>double>triple>ionic
bond strength
ionic>triple>double>single
Polyatomic ions
-certain atoms bond covalently with each other but are charged as a group. these are called polyatomic ion
-when p. ions bond with another ion it makes an ionic bond
To do lewis structures (+)
when positively charged subtract e-‘s
To do lewis structures (-)
when negatively charged add e-‘s
Resonance Structures
set of 2 or more Lewis structures that collectively describe bonding
Vesper theory
column 1 is non-polar (only have to do rows 1 2 and 3)
properties of ionic compounds
-Ionic compounds are called salts.
-They are brittle solids
Many ionic compounds dissolve in water
-Solutions with dissolved ionic
compounds are electrical
conductors (electrolytes)
-High melting/boiling points
