Liquids And Solids Essay, Research Paper
Liquids and Solids
How do the strengths of the intermolecular attraction compare btw solids, liquids, and gases at room temperature?
What is the difference btw intermolecular bonds and intramolecular bonds?
Explain how dispersion forces form.
Explain how dipole-dipole and hydrogen bonds form
How does viscosity change with increasing and decreasing temperature?
Why is boiling a cooling process
How does pressure effect the boiling point of a substance?
How do intermolecular bonds effect the boiling point of a substance?
Calculate the following Molarity prob: Make sure you know how to prepare the solutions.
Calculate the molarity of a solution prepared by dissolving 95.5 grams of KNO3 in enough water to make a 0.75 L solution.
How many grams of chlorine are needed to prepare a 0.50 liters of a 0.100 M solution of chlorine dissolved in water?
How do you make 2.5 L of HCl with a concentration of 3.0 M from a 12.0 M solution?
How many ml of an 18.0 M solution of sulfuric acid would you use to make 3.8 L of a 4.0 M solution?
According to Le Chantelier’s Principle, predict the direction the reaction will shift
2 NO (g) = 2 H2 (g) N2 (g) = 2 H2O (l)
(a) NO is added
(b) water is removed
(c) nitrogen gas is removed
(d) nitrogen gas is added
4 HCl (g) = O2 ( g) 2 H2O (g) = 2 Cl2 (g)
(a) oxygen is added
(b) hydrochloric acid is removed
(c) chlorine gas is added
(d) water is added
If the reaction shifts to the right, will the products of the reactants increase in concentration?
If the reaction shifts to the left, will the products of reactants increase in concentration?
Write a balanced equation showing the following dissolved in water
Sr(NO3)2
CaCl2
What would happen if you added calcium phosphate to the following equation?
Sr3(PO4)2 3 Sr2+ + 2 PO43-
Solutions and Equilibrium
What are ion-dipole attractions and how are they involved in the process of solvation
What does crystallization or precipitation mean?
What is a supersaturated solution? How is this kind of solution made?
What happens to the boiling point and freezing point of water when salt is added?
How can you increase the rate at which a solute dissolves in a solvent?
What kinds of compounds are electrolytes and why
What two processes are equal when solubility equilibrium is reached?
Carbon tetrachloride and water are immiscible in each other. Explain
How does temp effect the solubility of a gas and solid
Why do cities add salt to the roads in the winter?
When is a reaction at chemical equilibrium?
Chapter 15
Properties of Solutions
Solute
Solvent Example
Soluble
Insoluble Example
How can you tell which subs is the solute and which is the solvent
Types of Solutions
Solid Solutions
Alloys =
How are alloys formed?
Gaseous Solutions
Liquid Solutions
Miscible
Immiscible: Example
Aqueous Solutions
Aqueous solution = water as solvent
Electrolyte = substance that dissolves in water to form solution that conduct electricity
EX Why do electrolytes conduct electricity? Ionic compound
Non -electrolyte = substance dissolve in water doe not conduct electricity
Concentration of Solutions
A concentrated solution contains: Large amt. of solution to amt. of solvent
Ex punch syrup sugar to water
Dilute solution = small amt.
Concentration of a solution is amt. of solution to amt. of solvent
Molarity (M)
Most common expression of solution concentration
Number of moles to solvent dissolve in e? of solvent
molarity = moles of solvent
L of solution?
A volumetric flask is used to make solution of a precise molarity?
Practice problem
Vinegar is a solution of acetic acid. What is the molarity of the solution produced when 125 g of acetic acid (C2H4O2) is dissolved in sufficient water to prepare 1.5 L of solution?
1.3 grams
How many grams of bromine are needed to prepare 0.500 L of a 0.0100 M solution of bromine in water? .79 grams
Try to figure these out on your own.
M1V1 = M2V2 M = molarity V = volume (liters)
If you have a 12 M solution of HCl how many liters of it should you use if you want to make 2 liters solution of HCl with a molarity of 3 M?
You want to make a 7.5-L solution of 4 M sulfuric acid. You have 6 M solution available. What would you do?
Freezing Point Depression = colligative property which describe the ability of a solute to lower t
Ex slt
Why does it help to add salt to water cooking = increased the boiling point
On cold winter days unprotected radiator water can freeze and expand which can ruin the engine by cracking the engine block. Which antifreeze mixture would you want in your engine of a cold winter day? One with the lowest freezing point.
Chemical equilibrium
The concept of equilibrium
What is equilibria? 2 opposing processes take place at the same time
Reversible reactions products aft
Are all reactions reversible ex?
Yes some can’t do it on their own or haven’t been dis
What is the standard convention with a reversible reaction?
Chemical Equlibria= the rate at which the
What do chemist use to dente the concentration of a substance
It is important to recognize that reaching equilibrium does not mean that
Chemical equilbria is a constant or changing process
Le Chanteliers Principle =
Changes in Concentration
If more of a particular substance is added to a reaction at equilibrium, the reaction will return to equal by .. Consuming same of the added subs
If a substance was removed, the reaction will return to equil by .. Producing more of the subst that was removed
Practice Problems
Predict the direction of the shift in equil if : As4O6 + 6 C As4 + 6 CO
CO is added left
As4 is removed right
Which change will increase the production of water vapor in this reaction?
2 H2S + 3 O2 2 H2O + 2 SO2
a adding SO2
b removing H2S
c removing O2
d removing SO2
Chap 17 Solubility and Precipitation
Dissolution and Precipitation
Just as you did with chemical reaction’s, you can write an equation to show the dissolution (dissolving) os .. An ionic solid place in water
Write an equation showing the dissolving of Na Cl in water? .. NaCl (s) D Na (aq) + Cl (aq)
Write a balanced equation showing the dissolving of BaCl2 in water.. BaCl2 D Ba2 (aq) = Cl2- (aq)
Write a balance equation showing the Fe(OH)3 ???
Precipitate = the process in which ions have a solution
Solubility equilibrium =
The common ion effect = a shift in equilibrium that occurs
Practice prob
17-3 p580
Saturation
Saturated solution =
Chapter 14
Kinetic-molecular theory of matter explains the physical properties of liquids and solids.
(According to the kinetic-molecular theory, the state of a substance at room temp depends on the strength of the attractions between its particles.)
Intramolecular forces:
Covalent bonds exist within the molecule, holding the atoms together in a specific shape.
Intermolecular forces include:
Dispersion forces: Force of attraction between induced dipole. Temporary (- +).
Present in all molecular substances.
Dipole-dipole forces: Some molecules have a permanent (- +) charges.
Hydrogen bonds: Stronger bonds ( hydrogen, florine, oxygen, or nitrogen)
Large particle results in a strong bond.
Properties of Liquids
Surface tension
Viscosity
The Nature of Solids
Crystalline solid – highly ordered, repeating pattern
Example: Diamonds
Amorphous solid – without form (supercooled liquids)
Examples: Glass, rubber, plastic
Bonding in Solids – Physical properties of a solid depend on the dind of particles and the strength of attractive forces that hold them together. Types of bonds:
Metallic – metals
Molecular – organic compounds
Ionic – salts
Covalent-network solid – diamonds, graphite, silicon, quartz
Changes of State – To change state, must overcome bond.
Vaporization – change liquid to gas
Condensation – change gas to liquid
Sublimation – solid to gas (dry ice)
Deposition – gas to solid (snow, water vapor to solid)
Chapter 16
Concept of Equilibrium
Reversible reaction – chemical reactions in which the products can reform the original reactants.
2 NO2 (g) N2O4(g)
Chemical equilibrium is reached when the rate of the forward reaction is equal to the rate of the reverse reaction.
The Law of Chemical Equilibrium
Law of Mass Action – ratio of concentrations of reactants and products of a reversible reaction in terms of the equilibrium constant (Equilibrium expression)
Law of chemical equilibrium – every reaction that reaches equilibrium has a specific equilibrium constant, which indicates the extent of the reaction.
Equilibrium position – relates to the equilibrium concentrations of the component of a reaction and depends upon the initial concentrations.
Pure solids and liquids involved in heterogeneous equilibria do not appear in the equilibrium expression. Equilibrium constant. (do not change)
Reaction quotient (Q) – Used to determine if the reaction is at equilibrium. (Q = Keq)
Le Chatelier’s Principal – A system that is disturbed from equilibrium will shift in order to reduce the disturbance. Factors that disturb a system are change in concentration of reactants and/or products, changes in pressure or temperature.
Habor process industrial process ammonia, uses Le Chatelier’s Principal to maximize production of ammonia.
Chapter 17
Solubility Equilibria
When an ionic solid is placed in water, attractions between the polar water molecules and the ions of the solid cause the solid to dissociate.
The ions spread throughout the solution during dissolution.
At the same time the ions in the solution collide with the remaining ionic solid and become part of it during precipitation.
Dissolution and Precipitation are reverse processes.
A solution attains solubility when dissolution and precipitation occur at the same rate.
The ion concentration in solution are constant at equilibrium.
Precipitate – if the ion concentration is greater than the concentration at equilibrium (supersaturated)
Common ion – an ion contained in more than one solute in a solution.
Common ion effect – the solubility of an ionic solid added to a solution already containing a concentration of common ions is decreased.