UNIT 2- chemical bonds Flashcards
what is a chemical bond?
A chemical bond is the result of attracting/repulsive electrostatic forces between electrons and the nucleus of two atom
what are Covalent bonds?
- sharing electrons between non metal atoms (sim EN)
- tendency to gain electrons due to many valence electrons
- stronger than noncovalent
what is a polar molecule?
Combination of atoms with different electronegativity, shared electrons that is closer to the most electronegative element.
what is an ionic bond?
electronegative elements (non metals) and very electropositive elements (metals) .
how does an ionic bond form?
EP metal gives away electrons to the EN non metal = positive and neg ions that are attracted to eachother via electrostatic forces
what is Metallic bonding?
- similar electronegativity.
- It is an electroctatic atraction between a cloud of shared electrons
In metallic, ionic an covalent what is the electronegativity of boding like?
- metallic = similar
- covalent = similar
- ionic= very different
metallic bonds are responsible for:
- malleability,
- strength
- ductility
- thermal
- conductivity
what are the functional groups of Carbon?
H,O,N,P,S
what is the arrangement of carbon?
tetrahedral = 109.5 degrees
what are the 4 non covalent forms of bonding?
- ionic
- hydrogen
- van der waals
- hydrophobic
how is a hydrogen bond formed?
between EN Oxygen or nitrogen covalently bonded to Hydrogen
-stronger straight
how are van der waal forces formed?
2 uncharged atoms with electron clouds influencing eachtoher
how is a transient electron dipole formed?
- Random variations in the positions of the electrons around one nucleus
- which induces a transient, opposite electric dipole in the nearby atom.
- The two dipoles weakly attract each other, bringing the two nuclei closer. then repel
what is hydrophobic interactions?
nonpolar regions of amphipatic molecules (repel water) are held together by hydrophobic interactions
