A very basic inorganic Chemistry

BASIC CHEMISTRY

CIVL270-Maraqa


Units of Measurement
Basic

units and conversion factors

Quantity

SI Units

Conversion Factor

USCS Units

Length

m

3.2808

ft

Mass

kg

2.2046

lb

Temperature

o

C

1.8(oC)+32

Area

m2

10.7639

ft2

Volume

m3

35.3147

ft3

Velocity

m/s

2.2369

mi/hr

Flow rate

m3/s

35.3147

ft3/s

kg/m3

0.06243

lb/ft3

Density

Appendix A in the textbook contains conversion factors

o

F


Prefixes

CIVL270-Maraqa

Quantity

Prefix

Symbol

10-9

nano

n

10-6

micro

10-3

milli

µ
m

10-2

centi

c

10-1

deci

d

10

deka

da

102

hector

h

103

kilo

k

106

mega

M

109

giga

G


Periodic Table

Source: />
Appendix B in the textbook contains atomic weights of elements


What is Concentration?
The mass (or volume) of solute per unit mass (or volume) of solution.

+

=

Solute

Solvent

•Solid

•Liquid

•Liquid

•gas

•gas

Solution


Commonly Used Units of Concentration


For liquid
mass of solute
volume of solution

mass of solute
mass of solution


example

example

mg
L

mg
= ppm
kg

For dilute aqueous
solution
1 mg/L= 1ppm

For gases

volume of solute
volume of solution

example ppm (by volume)

mass of solute
volume of solution
CIVL270-Maraqa

example

mg
m3

The relation between
ppm and mg/l for
gaseous solutions
depends on pressure,
temperature and
molecular weight


The ideal gas Law: P V=n R T
Pressure

Volume

Gas constant
0.082 (L.atm/K.mol) (see Appendix C)
Temperature
(K=273+oC)
Number of moles

To convert from ppm to mg/m3 for gases use
mg ppm × molecular weight 273.15 K P (atm)
=
×
×
m3
22.414
T (K )
1 atm

Example 1.2
Convert 9 ppm CO to mg/m3 at 1 atm and 25oC.
Solution

CIVL270-Maraqa

mg 9 × 28
273.15 K
1 atm
=
×
×

= 10.3
3
m
22.414 (273 + 25) K 1 atm


Other Concentration Units
Molarity (M) =

moles of solute
volume of solution (L)

Moles of solute =

mass of solute
Molecular weight

mass of solute/L
Normality =
equivalent weight

Equivalent weight =

CIVL270-Maraqa

MW
equivalent number


Kinetics

xA

yC + zD

The rate of change of A with
respect to time, if the reaction is
irreversible, takes the form:
d[A]
= −k[A]a
dt

Concentration

Reactions take time to reach equilibrium. This time could
be very short or very long.

C
A
Time

Constant determined
experimentally.
Reaction
rate constant

Many reactions rates in the
environment are modeled d[A] = −k[A]a
dt
as first-order (i.e. a=1):

CIVL270-Maraqa

D

[A ] = [A o ]e − kt


Stoichiometry
Consider the following balanced chemical reaction

a X+ b Y

cZ

The equilibrium constant (K) for this reaction is defined as:
[ Z ]c
; [ ]= molar concentration.
K=
a
b
[ X ] [Y ]
If the chemical is in the solid state or pure liquid then its [ ]=1.
If the chemical is in the gaseous form, then its [ ]= its partial
pressure (P).


In-Class Exercise (Example 2.2 modified)
2 M of C6H12O6 are completely oxidized to CO2 and H2O. Find the amount of
oxygen required to complete the reaction.

Solution:
The balanced reaction is:
1C6H12O6 + 6O2

6CO2 + 6H2O

1C6H12O6 M requires 6O2 M
2 M requires

?O2 M

O2 = 6x2= 12 M
= (12 M)(32 g/mol)
= 384 g/L

Note: K for the above reaction is written as

[ H 2O(l ) ]6 [CO2 ( g ) ]6

6
PCO
2
K=
=
[O2 ( g ) ]6 [C6 H 12O6 ( aq ) ] PO62 [C6 H12O6 ( aq ) ]

CIVL270-Maraqa


Reactions

Transform

Chemical
 Coordination
partner transfer
Oxidation-reduction

Transfer

Biological
Aerobic degradation

Volatilization

Anaerobic degradation Sorption
Ion exchange
Sedimentation

CIVL270-Maraqa


Example Coordination Partner Transfer Reactions
Acid-base rxns
H2O
H+ + OH



Solubility product

CaCO3 (s)



[ H + ( aq ) ][OH − ( aq ) ]
K w=
= [ H + ][OH − ] = 10 −14 at 25o C
[ H 2O( l ) ]

Ca

2+
(aq)

(aq)

+ CO

Solubility of gases

CO2(g)

CIVL270-Maraqa

CO2(aq)

23 (aq)

K H=

2−

K sp= [Ca 2+ ][CO3 ] = 5 × 10 −9

[CO2 ( aq ) ]
PCO2

= 0.033 (mol / L.atm)


Solubility Product (Ksp)

Solubility of Gases (KH)

Equilibrium Equation

Ksp at 25oC

T(oC)

CO2

O2

CaCO3 = Ca2+ + CO3 2-

5×10-9

0

0.0764

0.00218

CaSO4 = Ca 2+ + SO4 2-

2×10-5

10

0.0532

0.00169

Cu(OH)2 = Cu 2+ + 2(OH)-

2×10-19

15

0.0454

0.00152

Al(OH)3 = Al 3+ + 3(OH)-

1×10-32

20

0.0391

0.00138

25

0.0333

0.00126

Ca3(PO4)3 = 3Ca

2+

CaF2 = Ca 2+ + 2F-

CIVL270-Maraqa

+ 4PO4

3-

1×10

-27

3×10-11

In-Class Exercise (Example 2.9)
Find the solubility of fluoride ions in water caused by the
dissolution of CaF2.

Solution
CaF2 (s)

Ca 2+ (aq) + 2F-(aq)

Ksp=[Ca2+][F-]2= 3x10-11
Assume [Ca] = s

[F]= 2s

(s)(2s)2=3x10-11
s= 2x10-4 mol/L
[F]= 2(2x10-4)= 4x10-4 mol/L
= (4x10-4 mol/L) (19 g/mol) (103 mg/g) = 7.6mg/L
CIVL270-Maraqa


Organic Chemistry
Organic

compounds contain carbon except compounds such as CO, CO 2,

CO3.

Organic compounds
compounds

Organic
Aliphatic
Aliphatic

Cyclic
Cyclic

Saturated
Saturated
(Paraffins)
(Paraffins)

Unsaturated
Unsaturated
(Olefins)
(Olefins)

Aromatic
Aromatic

Hydrocarbons:

Organic compounds that contain H and C.
Alkanes (single bond): Methane (CH ), Ethane (C H ) , Propane (C H ),
4
2 6
3 8
Butane (C4H10), Pentane (C5H12), Hexane (C6H14), Heptane (C7H16),
Octane (C8H18), Nonane (C9H20), Decane, (C10H22) etc.
Alkenes

(double bond): Ethene (C2H4), Propene (C3H6), etc.

Alkynes

(triple bond): Ethyne (C2H2), Propyne (C3H4), etc.


}

Examples
CH3 CH

CH3

CH3

CH2

CH2

CH3

CH3
Butane

2-methylpropane
CH3
CH3

C

Cl H

CH3
CH2

CH3

CH

Those compounds have the
same chemical formula
(C4H10) but different structure.
They are called isomers

CH3

Cl C

2,2,4-trimethyl pentane

Cl Cl
Cl C C F
F F
1,1,2-trichloro-1,2,2-trifluoroethane (CFC)

C H

1,1,1-trichloroethane

(TCA)

Cl H
Cl Cl
C

C

Cl H

Trichloroethylene (TCE)


Examples
H
H
C

C

C
H

C

=

C
C

CH3

H

CH3

Benzene

1,2-dimethyl benzene
(o-xylene)

H

H
CH3

CH3

Methyl benzene

1,3-dimethylbenzene

(Toluene)
CH3

(m-xylene)

CH3
CH3

1,4-dimethylbenzene
(p-xylene)

CIVL270-Maraqa


Organic Compounds with Functional Groups
•Alcohols: contain (-OH) group attached to aliphatic
H
H-C -OH

Methanol

H

•Phenols: contain (-OH) group attached to aromatic
OH

Phenol

•Aldehyde: contain

O

C-H

group

O

H-C-H Formaldehyde

CIVL270-Maraqa


•Ketones:

•Ethers:

contain
group with carbon
atom attached to carbon atoms

contain(-O-) group

O
-C -

O
H3C-C-CH3

acetone

•Carboxylic acids:
contain

O
-C -OH

group

O
-C-OH

H3C-O-CH3

Dimethyl ether

•Amines:
contain (-NH2) group
H3C-CH2-NH2

Benzoic acid
CIVL270-Maraqa

Ethyl amine


Organic Compounds of Environmental Concern








Trihalomethanes (THMs): These compounds are
present in chlorinated waters.
BTEX: benzene, toluene, ethylbenzene, and xylene.

Polynuclear Aromatic Hydrocarbons (PAHs):
naphthalane, anthracene, etc.
Polychlorinated Biphynels (PCBs).
Pesticides: Example dichlorodiphenyltrichloroethane
(DDT).

CIVL270-Maraqa