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Reactions of Ions and Molecules in Aqueous Solutions. BlakeH
Solution- a homogenous
mixture in which the
molecules or ions of the
components freely move
with each other. A
solution is made from a
solvent and a solute
Electrolytes
An electrolyte is when a
solute is put in an aqueous
solution it conducts
electricity.
This is because of a
process called dissociation
which means that when an
ionic compound.
Strong electrolytes exist
because the solute is
100% dissociated into
ions if it does not fully
dissociate then it is a weak
electrolyte or it can not
dissociate at all and not
become an electrolyte.
An acid is a substance that
forms a hydronium ion
(H3O) when mixed with.
A strong acid will be
100% ionized when
dissolved. If not, it is then
called a weak acid.
A base is a substance that
will form a hydroxide ion
when dissolved in water.
To form a hydroxide ion
molecular bases undergo
ionization.
Molarity(M)= Moles of Solute
Litres of Solution
Solvent- this is the medium in
which a solute or solutes are
mixed or dissolved. Most of
the time the solvent will be
water in the chapter which
forms aqueous solutions.
Dilute and Concentrated
A dilute solution has a low ratio
of solute to solvent.
Solute- this is the substance
dissolved into a solvent and it
is the substance that is in low
concentration.
Saturated Solutions
The saturation point of a
solution is the limit to the
amount of solute that can
dissolve into a solvent. If there
is more than the saturation point
then it is called supersaturated
and if there is less solute than
the saturation point it is called
unsaturated.
The temperature of a solution
changes the saturation point of
the solvent.
Ions with the symbol (aq) are
hydrated and in an ionic
equation they can be written
separately.
Na2SO4 (aq) →
+
2Na (aq) + SO42-(aq)
A concentrated solution has a
high ration of solute to solvent
M.E, T.I.E, N.I.E
M.E- shows the chemical equation balanced.
AgNO3 (aq) + KCl(aq) → AgCl(s) + KNO3 (aq)
T.I.E- Balanced chemical equation showing dissociated ions with charges.
+
+
+
Ag (aq) + NO3 (aq) + K (aq) + Cl (aq) → AgCl(s) + K (aq) + NO3 (aq)
N.I.E- Spectator ions (ions that do not take part in the reaction) are
removed.
+
+
Ag+(aq) + NO3 (aq) + K (aq) + Cl (aq) → AgCl(s) + K (aq) + NO3 (aq)
Ag
+
(aq)
-
+ Cl (aq) → AgCl(s)
Metal oxides for strong bases when added to water.
This causes the formation of metal and hydroxide
ions.
2+
CaO(aq) + H2O(aq) → Ca (s) + 2OH (aq)
Strong acids are also strong electrolytes here are
the most common:
HCl, HClO4, HNO3, HBr, HI, H2SO4
Also strong bases which are very soluble metal
hydroxides are also strong electrolytes:
IA hydroxides, Ca, Ba, and Sr hydroxides
Acid Salts
An acid salt will
exists if an ion is
capable of making
additional
hydrogen atoms.
Naming Binary Acids
When an acid is named as an aqueous solution
you take the first syllable of the element and
you place it within Hydro__ic acid
Ex
HCl
Molecular compound= Hydrogen Chloride
Binary acid= Hydrochloric acid
Naming Oxoacids
These are named accordingly to their
anion suffix.
Ends in -ate it is now –ic as an acid.
HNO3 = Nitric acid
Ends in ite it is now –ous as an acid
HClO2 = Chlorous acid
A Reaction will occur if……
-Neutralization- acid reacts with a base.
-two soluble reactants for a precipitate.
-a gas is formed.
-strong electrolytes produce weak electrolytes.
Metathesis Reaction
This is the other name for a double
displacement reaction:
- The charges of the reactant ions
produce the formulas of the
products
- Cations switch places
- AB + CD  AD + CD
Gas-Forming
This is when a metathesis reaction forms a gas.
HCN, H2S, H2CO3, H2SO3, NH4OH
Molarity Ex
10g NaCl dissolved into 75.0mL, M=?
10g NaCl x (1mol NaCl) x (moles of NaCl) = 2.28M
58.44g NaCl
0.0750L
Dilution Ex
12.1M HCl, 250.0mL of 3.2M HCl V=?
Vstock x 12.1M = 250.0mL x 3.2M
12.1M
12.1M
Vstock = 66mL
Titration
This is the controlled addition of a reactant
to a known amount of another substance.
An indicator is most commonly used to
signal when a reaction is complete.
Endpoint- the volume of the added reactant
(titrant) required to complete the reaction.
Molarity expresses the relationship
between the moles of solute and the
volume of the solution in Liters.
This is expressed in moles of solute per
Liter of solution.
Dilution
The process of dilution is to add more
solvent to the mixture to decrease the
concentration of solute present. While
the amount of solvent increases so does
the volume but not the moles of solute.
CstockVstock = CnewVnew
C = Concentration
V = Volume
Solve Titration
-Balance equation
-Calculate moles of known component
-Soichiometry to find unknown
-convert moles found into another quantity
if needed.
Stoichiometric Calculation
V of 2M HCl is needed to react with 25.3g of Na2CO3 completely?
25.2g Na2CO3 x 1 mol Na2CO3 x 2 mol HCl
x
L
1
105.90g
1 mol Na2CO3
2 mol HCl
= 0.238 L