chapter 8 solutions 5% glucose and 0.9% saline solutions are used in iv therapy
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Chapter 8 Solutions
5% glucose and 0.9%saline solutions are usedin IV therapy
Understanding solutionproperties help in solving environmental problems.
All of the following are solutions except:
a.airb.steelc.vinegard.milke.bleach
Do you really know what a solution is?
It is a homogeneous mixture ctg. one or more solutes dissolved in a solvent.
What is a solution?
Solid K2Cr2O7 will be the solute and waterwill be the solvent .
This is a potassium dichromate solution.
Types of Solutions
Solutions: Physical States
Solid Liquid Gas(brass) (bleach) (air)
Brass is a homogeneous solution. Granite is a heterogeneous
mixture.
What is the major solute in bleach?
What is the solvent?
O2 is the major solute and N2 is the solvent in air.
Example: Air is a gaseous solution.
Classification of Liquid Solutions
Unsaturated Saturated Supersaturated
ConcentratedDilute(tend to be opaque)(transparent)
(maximum solute) (the maximum limit is exceeded)
(less than maximum solute)
Bleach ( ~ 5% NaOCl)
Vinegar ( ~ 5% CH3COOH)
Peroxide ( ~3% H2O2)
Most household products are unsaturated dilutesolutions.
08_T01.JPG
Tests for a Solution
Liquid solutions can pass the following tests:
(a) Can pass thru a filter with no residue
(b) Does not scatter a light beam
(c) Does not form a ppt when centrifuged ( i.e.particles do not settle)
(d) Dilute solutions have a clear/uniform appearance
Tests for a Solution
p. 193
Solutions leave noresidue when filtered.
Light is not scatteredby a solution
Dilute solutions are clear.
Practice Exercises on Solutions
Is the contents of the coke bottle asolution?
p. 193
Is the beer as shownin this mug a solution?
p. 192
Is the mixture in the beaker a solution?
p. 200
Whole Blood
Is this a solution?
p. 200
Blood is not a solution .
p. 207
Are these sports drinks solutions?
Are these solutions?
Flask A Flask B
Is this a solution?
Is this mixture of water and ether a solution?
Is gasoline a solution?
Practice Exercise on Differentiatingthe Solute and the Solvent
Solution Solute Solvent
10.0 g of potassium chloride
dissolved in 70.0 g of water
80.0 g of ethyl alcohol
added to 50.0 g of water
60.0 g of CaBr2 and 25.0 g of AgNO3 dissolved in 100.0g of water
40.0 mL of ethanol dissolved in 40.0 mL of methanol.
Common Types of Solutions
Error Check: True or False?
All solutions are homogeneous mixtures
Every part of a solution has exactly the same properties as every other part
All solutions have a variable composition.
Electrolytes ( We get to this on Wed)
Solubility
What vitamins arewater soluble?
What vitamins are fat-soluble?
What is solubility ?
Solubility is the grams of solute per 100g of H2O at 25C
Solubility is affected by:
•Temperature
•Polarity of the solvent and solute
•Particle size of the solute
•Pressure when gases are involved
Effect of Temperature on Solubility (Solids)
Effect of Polarity
“ like dissolves like”
Polar solutes prefer polar solvents ….
..and the same for nonpolar solutes/solvents
What does “like dissolves like” mean?
Predict the solubility of CH3COOH in H2O
a.Very solubleb.Moderately solublec.Slightly solubled.Insoluble
Effect of Polarity
CH3COOH (acetic acid)is the active ingredient in vinegar… it is very solublein H2O.
Effect of Polarity
Predict the solubility of oil (CnH 2n +2) in H2O
a.Very solubleb.Moderately solublec.Slightly solubled.Insoluble
Effect of Polarity
Predict the solubility of CH3CH2OCH2CH3
in H2O
a.Very solubleb.Moderately solublec.Slightly solubled.Insoluble
Gasoline and water are not miscible. Why?
Gasoline is nonpolar and water is polar.
Solubility Rules
Solubility Rules
p. 193
Practice Exercise: Identify the solublecompound(s) in each set.
1.KHCO3, K2CO3, KOH, KI, K3PO4
2. Ba(OH)2, BaSO4, BaCO3, Ba(NO3)2
3.NaCl, AgCl, BeCl2, CuCl2
4.NH4NO3, PbSO4, AgNO3, Ni(OH)2
What is the effect of temperature and pressure on gas solubility?
Effect of Temperature on Solubility (Gases)
Effect of Pressure on Solubility (Gases) (Henry’s Law)
Henry’s law states:
The solubility of a gas is proportional to its partial pressure .
Effect of Pressure on Solubility of Gases (Henry’s law)
Start End Increase Pressure
How would Henry’s Law apply in the case of the blood gases in deep-sea divers.
Solubility increases with higher pressure and vice-versa.
Pressure and the Solubility of Gases (Henry’s law)
Pressure (atm)
Solubility of CO2
( g/100mL water)
1 0.348
2 0.696
3 1.044
Solution Formation
How does an ionic compound dissolve in water?
NaCl(s) Na+(aq) + Cl (aq)Add H2O
s = solidaq = aqueous
Start
NaCl Dissolving in H2O
Halfway End
The ions become hydrated by the water molecules.
A hydrated ion is an ion surrounded by H2Omolecules.
This is a hydrated Na+ ionThis is a hydrated Cl- ion.
The rate of solution formation is determined by:
(a)Particle size
(b)Temperature
(c) The amount of agitation
Preparing Solutions of Known Concentrations
Volumetric flasks are used to prepare solutions.
Concentrations are defined as the amountof solute dissolved in an amount of solution
Solution Concentrations
PercentMolarity
volume percentmass percent mass-volume percent
Percent Concentrations
Mass/Mass Example
Prepare 225g of a 6.00 %(m/m) KCl solution
%(m/m) = g solute
g solution
x 100
Reminder: solution = solute + solvent
Prepare 225g of a 6.00 %(m/m) KCl solution
6% = ?g solute
225g solution x 100
Mass/Volume Example
How many grams is required to prepare 250.0 mL of a 12.0% (m/v) glucose solution.
Practice Exercise—Percent : How many gramsor mL are needed to make the following solutions?
200.0 mL of 0.8%(m/v) NaOH
300.0 mL of 34.0% (v/v) methanol CH3OH
150.0 g of 2.5% (m/m) KOH
Molarity is an important concentration used in the chemistry lab.
M ( molarity ) = mol (moles of solute)
L ( liters of solution)
For example, what is does a 3.0 M HCl solution mean?
What does a 0.1M AgNO3 solution mean?
Practice Exercise—Molarity : How many moles are needed to make the following solutions?
1 L of 4.0 M NaOH
250 mL of 3.5 M KI
Start morning2.0 L of 3.5 M CaCl2
Practice Exercise—Molarity : How many grams are needed to make the following solutions?
1 L of 4.0 M NaOH
250 mL of 3.5 M KI
2.0 L of 3.5 M CaCl2
Write a brief set of instructions for preparing250 mL of a 6.8% (m/v) glucose solution.
relax and get organized
write the correct formula
use the formula toget the g of solute
write the instructions
1 2 3
4
The grams of glucose required is 17 grams.
In a 250-mL volumetric flask dissolve 17 g of glucose in d.w. and dilute to the mark. Mix well.
Note: Volumes are not equal when mixing different liquids.
Can the marbles fit in the large beaker?
Preparing Dilute Solutions
Start with a “stock solution:
Dilute Solution Formula
concentration of stock solution x volume of
stock solutionconcentration of diluted solution= x volume of
diluted solution
xCs Vs = xCd Vd
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