Periodicity and Atomic Structure Flashcards
Describe the trend of first I.E.
Increases across a period and decreases down a group.
Reason for I.E increasing across a period.
Increased nuclear charge / attraction.
Reason for I.E decreasing down a group.
Increased shielding and distancing effect.
Reason for unexpected decrease in I.E (i.e not down a group).
New electron structure would have a more stable completely empty or exactly half full electron sub level.
Name four types of chemical bonds.
Ionic, covalent, dative, metallic.
Name three types of physical bonds, in order of strongest to weakest.
- Hydrogen bonds
- Dipole-dipole interaction
- Van der Waals forces.
Define electronegativity.
A measure of the attractive force of the nucleus of an atom on a shared electron pair in a covalent bond
Define a dative bond.
A type of covalent bond where a shared electron pair consists only of electrons from one atom.
How are sp3 orbitals formed?
when one s orbital and 3 p orbitals combine it produces 4 sp3 orbitals.
How does a pi bond form.
By the overlapping of two p orbitals from the atoms in the pi bond.
What is the difference between intermolecular forces and intramolecular forces.
Intermolecular forces link molecules together.
Intramolecular forces link atoms together within a molecule.
Which elements are capable of H bonding?
N, F, and O.
To which four elements does the octet rule apply to without exception?
C, N, O, and F.
Shape and bond angle of 2 electron pairs around an atom.
Linear. 180 degrees.
Shape and bond angle of 3 electron pairs around an atom.
Trigonal planar. 120 degrees.
Shape and bond angle of 4 electron pairs around an atom with no lone pairs.
Tetrahedral. 109.5 degrees.
Shape and bond angle of 4 electron pairs around an atom with 1 lone pair.
Trigonal pyramidal. 107 degrees.
Shape and bond angle of 4 electron pairs around an atom with 2 lone pairs.
V-shaped. 105 degrees.
Shape and bond angles of 5 electron pairs around an atom.
Trigonal bipyramid. 90 and 120 degrees.
Shape and bond angle of 6 electron pairs around an atom.
Octahedral. 90 degrees.
Describe the trend for atomic radius.
Decreases down the period. Increases down the group.
Reason for atomic radius decreasing down a period.
Despite increased electrons, increased nuclear charge pulls electrons tighter.
Reason for atomic radius increasing down a group.
Despite increased nuclear charge, increased shielding and added valence electron shells expand radius.
