What needs to happen for a reaction to occur?
reactants must come into physical contact
What phase does reactions happen best in?
gas or liquid
b/c more movement occurs
What is a homogeneous mixture?
two or more components mix freely
molecules or ions are completely intermingled
contain at least two substances
What is the medium that dissolves the solute?
solvent
What is the substance dissolved in solvent?
solute
What is the component is large amounts in a solution?
solvent
What does an aqueous solution mean?
a solute dissolved in water as the solvent
A method characterizing solution broadly defined as a solute to solvent ratio, though the method of measurement can change?
concentration
Formula for the concentration?
C = solute / solvent
What is a concentration called when the solution is a small solute to solvent ratio?
Give example
dilute solution
eye drops
What is a concentration called when the solution is a large solute to solvent ratio?
Give example
concentrated solution
brine
Why do you have to be careful when you use ‘dilute’ and ‘concentrated’ ?
they are relative terms
What do chemists use as a unit of absolute concentration?
M = molarity
What are the units for molarity (M)?
moles / liter
Formula for solute
g solute needed to make saturated solution / 100g solvent
What does solubility depend on?
temperature
also the type of solvent
Solution in which no more solute can be dissolved at a given temperature?
saturated solution
Solution containing less solute than the maximum amount (able to dissolve more solute)?
unsaturated solution
Solution that holds more than the maximum solute because its temp went up, solute was added, and then the temp cooled?
super saturated solution
What does it mean for a solution to be an electrolyte?
it conducts charge
Which compounds conduct electricity and which ones do not?
ionic compounds do
molecular compounds do not
What is a strong vs weak electrolyte?
strong = conducts electricity well weak = conducts electricity but not well
What happens when molecular compounds dissolve in water?
particles are surrounded by water
do not dissociate
What happens when ionic compounds dissolve in water?
water arranges itself around ions snd removes lattice (bonds?)
dissociate
(unless its a polyatomic)
What is dissociation?
salt breaks apart into ions when entering solution
What conducts electricity when ionic compound dissociate?
the separated ions
What do ionic compounds dissolved form?
hydrated ions
What does hydrated mean?
surrounded by water
How are ions indicated in a chemical equations?
aqueous (aq) written behind it
or
the ions are separated
What equation has substances listed as complete formulas?
molecular equation
What equation has all soluble substances broken into ions?
ionic equation
What equation only lists substances that actually take part in the reaction?
net ionic equation
What do net ionic equations get rid of from ionic equations?
spectator ions
What equation gives the identity of all compounds?
molecular eqation
What dissociates into ions?
All strong electrolytes
What equation is used to visualize what is actually occurring in solution?
ionic equation
What are spectator ions?
ions that don’t take part in reaction
they sit and watch
What equation emphasizes the actual reaction?
net ionic equations
What equation focuses on the chemical change that occurs?
net ionic equations
What is the criteria for ionic and net ionic equations?
material balance - same # of atom on both sides
electrical balance - same net electrical charge on both sides
What type of reaction is when two ions change partners?
metathesis / double replacement reaction
What type of reaction is when one ion changes to the other ion in the equation?
single replacement reaction
Give a sample formula for metathesis?
Give sample for single replacement?
AB + CD –> AD + BD (cation always go with anion)
AB + C –> A + CB
When does metathesis reactions occur?
solid liquid gas weak electrolyte non-electrolyte
*if one of those forms as a product
(if not then it doesn’t react and all ions are spectator ions)
Name the Solubility Rules
- all salts of alkali metal (G1A)
- all salts containing NH4(+) , NO3(-) , ClO4(-), ClO3(-) , C2H3O2(-)
- all chlorides, iodides, and bromides
* except with Ag(+) , Pb(2+) , Hg2(2+) - all salts containing SO4(2-)
* except with Ca(2+) , Sr(2+) , Ba(2+) , Hg2(2+) , Pb(2+)
Name the Insolubility Rules
- all metal hydroxides and metal oxides [OH(-) and O(2-)]
* except with G1A , Ca(2+) , Sr(2+) , Ba(2+) - all salts containing PO4(3-) , CO3(2-) , SO3(2-) , S(2-)
* except G1A and NH4(+)
Acids and Bases are common lab Reagan’s…name some common household acids and bases?
acids - vinegar, citrus juice, cola
bases - drain cleaners, ammonia
What is an Arrhenius Acid?
substance that reacts with water to produce hydronium ion, H3O(+)
What is an Arrhenius Base?
substance that reacts with water to produce the hydroxide ion, OH(-)
Give example equation for Arrhenius Acid…
HA + H2O –> A(-) + H3O(+)
Give example equation for Arrhenius Base…
metal hydroxide –> metal + hydroxide
NaOH (s) –> Na(+)(aq) + OH(-) (aq)
Name the Strong Acids
HClO4 (Perchloric acid) HCl (Hydrochloric acid) HBr (Hydrobromic acid) HI (Hydroiodic acid) HNO3 (Nitric acid) H2SO4 (sulfuric acid) ^^all aqueous
What is the electrical conduction dissociation of strong acids and bases?
good electrical conduction dissociate completely (aq)
Name the Strong Bases
G1A metal hydroxides LiOH NaOH KOH PbOH CsOH
G2A metal hydroxides
Ca(OH)2
Sr(OH)2
Ba(OH)2
What is the electricity conduction of weak acids and bases?
weak electrolyte
What strength is acetic acid?
What is it?
weak
CH3COOH (aq)
CH3COO(-) (aq)
What is it called when 2 opposing reactions are occurring at the same rate?
Dynamic Equilibrium
Chemical Equilibrium
What is it called when concentrations of substances present in solution do not change with time?
equilibrium
What is it called when both opposing reactions occur continuously?
dynamic
How are dynamic equilibrium equations represented?
a double arrow
In a dynamic equilibrium reaction…which reaction forms what?
forward reaction = forms ions
backward reaction = reverse ions
Do weak acids and bases dissociate?
weak acids = yes
weak bases = no
Write basic formula for a STRONG ACID IN WATER
HA (aq) + H2O –> H3O(+) + A(-)
Write basic formula for a STRONG BASE ex:M(OH)n
M(OH)n –> M(n+) (aq) + nOH(-) (aq)
Write basic formula for a WEAK ACID IN WATER
HA (aq) + H2O H3O(+) + A(-)
Write basic formula for a WEAK BASE IN WATER
B (aq) + H2O HB(+) (aq) + OH(-) (aq)
What is a neutralization reaction?
reaction that results is production of water and salt
product is neither acidic or basic
HA +BOH –> AB + H2O
neutralization reaction between STRONG ACID and STRONG BASE
2HCl + Ca(OH)2 (aq) –>
2HCl + Ca(OH)2 (aq) –> 2H2O (l) + CaCl2 (aq)
neutralization reaction between WEAK ACID and STRONG BASE
HC2H3O2 (aq) + NaOH(-) –>
HC2H3O2 (aq) + NaOH(-) –> H2O (l) + NaC2H3O2(-)
neutralization reaction between STRONG ACID and WEAK BASE
HNO3 (aq) + NH3 (aq) –>
HNO3 (aq) + NH3 (aq) –> NH4NO3 (aq)
neutralization reaction between WEAK ACID and WEAK BASE
HC2H3O2 (aq) + NH3 (aq) –>
HC2H3O2 (aq) + NH3 (aq) –> NH4C2H3O2 (aq)
What are oxidation-reduction reactions?
electron transfer reactions
- from 1 substance to another
What is another name for oxidation-reduction reactions?
redox reactions
When do redox reactions occur?
combustion of fuels
metal reacting with oxygen
What are the 2 processes of redox reactions?
oxidation = loss of electrons
reduction = gain electrons
LEO goes GER
What is the oxidizing agent?
What is the reducing agent?
ox=substance that accepts electron
re=substance that donates electrons
Split into half reactions
2Na + Cl2 –> 2 Na(+) + 2Cl(-)
reduction half reaction
Cl2 + 2e(-) –> 2Cl(-)
oxidation half reaction
Na –> Na(+) + e(-)
What use happen for redox reactions to occur?
one substance must accept the electrons lost by another
Can oxidation numbers be fractions?
yes but not common
What is oxidation state?
oxidation #
List then hierarchy of asigning Oxidation Number
- oxidation numbers must add to = charge of unit
- atoms of free elements have oxidation numbers of 0
- metals in G1A, G2A, and Al have ox. numbers of +1 , +2 , +3
- H and F in compounds have +1 , -1 ox. numbers
- oxygen has a ox. number of = -2
- G7A elements have ox. number of -1
- G6A elements have ox. number of -2
- G5A elements have ox. number of -3
- when there is a conflict between rules, use rule with lower ox. number or higher on list
How do you know if a single replacement reaction will take place?
looking at the metal activity series
Is the top or bottom of the metal activity series list more reactive?
the top
meaning the higher ones displace lower ones
the more active element must be by itself equation
What equations do you use to figure of the molarity or volume of a dilute or concentration solution?
(V1)(M1) = (V2)(M2)
1 = dilute 2 = concentrated