Chem 1a‐ Study Guide 1 Kinetic Molecular Theory: • All matter is composed of tiny particles • Particles are in constant motion • Inc T = inc motion (T α P) • Solids, gasses, liquids differ in structure, motion, attrxn Solid state: Inc T = Inc in ave velocity; thus inc in momentum (mass∙velocity) average, thus inc in average force per collision, thus pushes particles farther apart, thus inc in the vol of the solid Evaporation of a liquid: • Every particle eventually goes to surface • If the particle has enough momentum to inc the distance bxn itself from the attrxn of the other particles at the surface, then the particle will escape Condensation of a gas to a liquid: • At high T: No significant attrxns bxn particles • At low T: less momemtum, stronger attrxn, harder to break those attrxn • Eventually particles form into clumps & there is a significant amt of attrxns, thus forming a liquid Intermolecular attractions Non polar Even distribution of +/‐ charge
Polar Uneven distribution of +/‐ London Forces Always nonpolar Hydrocarbons molecular (CaHb) compounds Hydrogen bonds H w/ NOF NH3 Dipole dipole Polar molecules HCl Identifying chemical bonds ∆
0.4 Non polar covalent ∆ 0.4 1.7 Polar covalent ∆ 1.7 Ionic Metal‐
Usually Molecular compound Nonmetal ionic bond Nonmetal‐
Covalent Ionic compound nonmetal Prefixes for binary covalent compounds 1 mono 6 hexa 2 di 7 hepta 3 tri 8 octa 4 tetra 9 nona 5 penta 10 deca 2.54
1.057
Conversion factors to remember
453.6
1 3.785
47.2
1
47.2%
100
1
1
Ferrous
Ferric
Cuprous
Cupric
1 more O
1 less O
2 less O
1 more O
1 less O
2 less O
Group 4A
4 bonds 0 lone pairs Carbon (C) Metals w/ two possible charges
Fe2+
Iron(II)
3+
Fe
Iron(III)
Cu+
Copper(I)
Cu2+
Copper(II)
Naming oxyanions (root)=Nitrate
Per(root)ate
pernitrate nitrate (root)ite
nitrite Hypo(root)ite hyponitrite
NO4‐
NO3‐
NO2‐
NO‐
Naming oxyacids (root)=Nitrate
Per(root)ic
pernitric acid
nitric acid (root)ous
nitrous acid
hypo(root)ous hyponitrous acid
HNO4
HNO3
HNO2
HNO
Most common bonding patterns
Group 5A
Group 6A Group 7A
3 bonds 1 lone pair Nitrogen (N) Phosphorus (P) 2 bonds 2 lone pairs Oxygen (O) Sulfur (S) Selenium (Se) 1 bond 3 lone pairs Fluorine (F) Chlorine (Cl) Bromine (Br) Iodine (I) London forces: • Chance or collisions cause nonpolar molecules to form instantaneous dipoles which induce other nonpolar molecules to form instantaneous dipoles • London forces are the attrxns bxn the partial positive ( +) & partial negative ( ‐) charges in these instantaneously induced dipoles Thought process: • Larger molecules are able to induce more dipoles, have more e‐ & bigger e‐ clouds Æ e‐ are further away from nucleusÆ easier to distort e‐ cloud Æ creates more instantaneous dipolesÆ larger charges on both instantaneous/induced dipoles Æ stronger attrxns bxn dipoles Æ stronger London forces Polar molecules & London forces: • Chance or collisions causes polar molecules to become more polar • More higher polar molecules induce less polar molecules to become more polar • The more polar molecules can induce higher polarity in other less polar molecules resulting in an overall greater polarity bxn all molecules • London forces are the attrxns bxn the partial positive ( +) & partial negative ( ‐) charges in these instantaneously induced dipoles