Pre-Chemistry

what are the 2 most common metalloids you will see in gen chem?

Ge (Germanium) & Si (Silicon)

how do you determine the number of lone pairs for the central element when drawing Lewis Structures?

LP= (VE-8n/2)

Molecules that contain H bonded to N, O, F are ____

polar

hydrocarbons are _____

nonpolar

what are the forces/bonds ranked in strength?

1) ionic bonds

2) covalent bonds

3) metallic bonds

4) hydrogen bonds(IMFs)

5) Van de Waals (London dispersion forces are a type)

steps to balancing equation

1) metals

2) non-metals
3) H

4) O

to measure the strength of the acid, what do you measure?

measure the hydronium (H3O+) concentration

redox reaction

process that involves transfer of electrons

what types of reactions are always redox reactions?

combustion & single replacement reactions

what type of reaction is NEVER redox?

double replacement reaction

strong acid vs weak acid

strong acid→ release all their H+ ions
weak acid→doesnt release all H+

strong base vs. weak base

strong base→ release ALL OH- ions
weak base→ doesnt release all OH-

what is a hydrogen bond?

H bonded to more electronegative N,O,F

(between 2 molecules like 2 water molecules)

London Dispersion Forces?

what conditions can increase LDFs?

very weak and temporary bonds that are in ALL molecules(especially non-polar)

LDFs increase with

1) # of electrons

2) boiling point

3)surface area

what increases solubility (rank them in order)

1) more hydrogen bonds

2) more electrons
3) most SA

for stoichiometry, how do you find the Limiting Reactant& Excess Reactant

Convert each of the reactants into the mols of the product to see which one is less

how do you balance a redox equation in ACIDIC solution

1) write half reactions in which you add H2O to side with less O

2) add H+ when needed

2) balance the charges

how do you balance a redox equation in BASIC solution

1) write half reaction & add H2O to side with MORE O

2) add OH- where its needed

3) balance charges