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Transcript of As temperature increases, the molecules velocity increases, increasing the pressure on the...
Test 6 Review
As temperature increases, the molecules velocity increases, increasing the pressure on the container.
States of Matter
State Shape Volume Compressible?
Flows?
Solid Definite Definite No No
Liquid Indefinite
Definite No Yes
Gas Indefinite
Indefinite
Yes Yes
Critical Point – above this temperature, no amount of pressure can liquefy it.
Triple Point – all three phases are in equilibrium
Phase Diagrams
Homogeneous mixtures
Solvent – the substance there is more of; it does the dissolving.
Solute – the substance there is less of; it is being dissolved.
Solute is dissolved in solvent
Solutions
Are all things soluble?◦ No
Polar solvents dissolve polar solutes.◦ Ex: water (polar)
Non polar solvents dissolve non polar solutes.◦ Ex: oil (non polar)
“Like Dissolves Like”
Intermolecular Forces
Temperature
Pressure◦ For gases
What states of matter are required to form solutions?◦ Any: solid, liquid or gas
Factors Determining Solubility
Heating
Stirring
Crushing
One exception: gases dissolve better in colder temperatures.
How do you increase rate of dissolving?
Solubility of gas increases with pressure
Henry’s Law
Solubility – the amount of solute that will dissolve in a given amount of solvent at a given temperature.
Saturated Solution – solution that contains all the solute it can at a given temperature.
Unsaturated Solution – solution that contains less than the saturated amount of solute.
Supersaturated Solution – solution that contains more solute than it could normally hold.
Every compound has its own solubility curve.
Typically, when heated, solubility will increase
Solubility Curves
Acids produce hydrogen ions
HCl H+ + Cl-
Bases produce hydroxide ions
NaOH Na+ + OH-
Arrhenius Theory
H+
OH-
Acids donate protons (+)
Bases accept protons (+)
Conjugate acid – particle formed when a base gains a hydrogen ion
Conjugate bases – particle that remains when an acid has donated a hydrogen ion
Conjugate acid-base pair – 2 substances that are related by the loss or gain of a single hydrogen ion◦ Ex: NH3 and NH4
+
Bronsted- Lowry Theory
HCl(g) + H2O(l) Cl-(aq) + H3O+(aq)
Acid Conj. AcidConj. BaseBase
Acid + Base Conj. Base + Conj. Acid
NH3(g) + H2O(l) NH4+
(aq) + OH-(aq)
AcidBase Conj. BaseConj. Acid
Taste sour pH from 0-6.99 Has H+ at the beginning of the formula Produce H2(g) when reacting with most metals Neutralize bases Conducts electricity (because they contain
electrolytes) Turns litmus paper red
Characteristics of Acids
HCl hydrochloric acid
HBr hydrobromic acid
HI hydroiodic acid
HNO3 nitric acid
H2SO4 sulfuric acid
HClO4 perchloric acid
Strong acids that ionize completely
The stronger an acid, the weaker its conjugate base and vice versa.
Taste bitter pH between 7.01-14 Have OH- ions Feels slippery Neutralize acids Turns litmus paper blue
Characteristics of Bases
LiOH lithium hydroxide NaOH sodium hydroxide KOH potassium hydroxide RbOH rubidium hydroxide CsOH cesium hydroxide Ca(OH)2 calcium hydroxide Sr(OH)2 strontium hydroxide Ba(OH)2 barium hydroxide
Mg(OH)2 magnesium hydroxide◦ Milk of magnesia, it is not completely soluble, but
what does dissolve is a strong base.
Strong Bases
Anion Acid Name Example
-ide hydro—ic HCl hydrochloric acid
-ite --ous HNO2
nitrous acid
-ate --ic HNO3
nitric acid
Naming Acids
**only binary acids use “hydro”
H2SO4
HF
H3PO4
H2SO3
H2CO3
HNO3
Try these. . .Sulfuric AcidHydrofluoric AcidPhosphoric Acid
Sulfurous Acid
Carbonic Acid
Nitric Acid
Monoprotic – has 1 hydrogen◦ HCl
Diprotic – has 2 hydrogens◦ H2SO4
Triprotic – has 3 hydrogens◦ H3PO4
Categories of Acids
Always form a salt and water
Salt – a crystalline compound formed form an acids anion and a bases cation.
Neutralization Reactions
HCl(aq) + NaOH(aq) NaCl(s) + H2O(l)
Can act as either an acid or a base
Water is amphoteric
Amphoteric
Acid pH<7 Base pH>7[H+] pH pOH [OH-]
1410 OHH
14 pOHpH
Once you have 1 item, you can get any other one.
An unknown concentration of acid or base can be determined by measuring the amount of known acid or base that will neutralize the unknown.
An indicator changes color when the “end point” or neutralization occurs
Titration
Standard solution◦ Solution in which the concentration is known
End point◦ The point at which equivalent amounts of
reactants are present
For one to one ratios
For non one to one ratios◦ Need to calculate a mole ratio.
bbaa VMVM
L
molM molVM
If 15.0 mL of 0.500M NaOH is used to neutralize 25 mL of HCl, what is the concentration of the acid?
NaOH + HCl H2O + NaCl Since the ratio is 1:1, use MaVa=MbVb
(0.500M)(15.0mL)=Mb(25.0mL)
Mb=0.300M HCl
Practice
Alternative
L
xM
015.0500.0 x = 0.0075 mol NaOH
molNaOH
molHClmolNaOH
1
10075.0 0.0075 mol HCl
L
molM
025.0
0075.00.300M HCl
A 25 mL solution of H2SO4 is completely neutralized by 18 mL of 1.0M NaOH. What is the concentration of the acid?
NaOH + H2SO4 H2O + Na2SO4
Practice
2 1 12
L
xM
018.00.1 x = 0.018mol NaOH
molNaOH
SOmolHmolNaOH
2
1018.0 42
0.0090mol H2SO4
L
mol
025.0
0090.00.36M H2SO4
Can absorb moderate amounts of acid or base without a significant change in pH
Consists of a weak acid and its salt or a weak base and its salt.
Example◦ Acetic acid: HC2H3O2
◦ Sodium acetate: NaC2H3O2
Buffers
How it works
HA H+ + A-
HA H+ + A-
Strong Acid
Weak Acid
Lots of H+, very little HA
Lots of HA, very little H+