Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CIVL 7062 - Water Quality > Chemical Characteristics of Water > Flashcards

Chemical Characteristics of Water Flashcards

1
Q

What are the four main sources for inorganic and organic species?

A

1) Contact of water with minerals, rocks, and soils

2) Rain in contact with the atmosphere

3) Decomposition of organic matter in the environment

4) Municipal, industrial, agricultural and human activities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the main inorganic constituents?

A

Cations: calcium, magnesium, sodium, potassium (Ca2+, Mg2+, Na+, K+)

Anions: carbonate, bicarbonate, sulphate, chloride, nitrate (CO32-, HCO3-, SO42-, Cl-, NO3-)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What causes hardwater?

A

Calcium and Magnesium (Ca2+ and Mg2+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the typical order for arranging cations and anions in the meq/L graphical representation of possible pairs?

A

Cations: Ca2+, Mg2+, Na+, K+, anything else

Anions: HCO3-, SO42-, Cl-, anything else

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the point of the graphical representation of pairs?

A

To make sure the sum of meq/L of cations is equal to that of the anions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens to inorganic compounds in water?

A

They dissociate into ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 3 inorganic constituent indicators?

A

pH
Alkalinity
Hardness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is alkalinity?

A

A measure of water’s capacity to neutralize acids (ability to absorb H+ without significant pH change)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the major contributors to alkalinity?

A

Bicarbonate, carbonate, and hydroxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the typical units of alkalinity?

A

meq/L
mg/L as CaCO3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the typical pH value for phenolphthalein alkalinity?

A

8.3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

A pH value below 8.3 usually means there is no carbonate present as it has been converted to bicarbonate, true or false?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A pH value below 4.5 usually means there is no bicarbonate present as it has been converted to carbonic acid, true or false?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Hardness is cause by what?

A

Multivalent Cations
(mainly calcium and magnesium in natural waters)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What would happen if you tried to wash dishes with hard water and soap?

A

The hard water would reduce the soaps cleaning action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the most common and troublesome form of hardness?

A

Calcium Bicarbonate (Ca(HCO3)2

It is picked up by rain water passing through limestone

17
Q

What is total hardness?

A

The combination of calcium and magnesium hardness

18
Q

What are the units of hardness?

A

mg/L of CaCO3

19
Q

What ions mainly contribute to temporary hardness?

A

Bicarbonate and Carbonate
(HCO3- and CO32-)

20
Q

What is carbonate hardness?

A

The combination of bicarbonate and carbonate hardness
(also known as temporary hardness)

21
Q

What ions mainly contribute to permanent hardness?

A

Chloride and Sulfate
(Cl- and SO42-)

22
Q

What is non-carbonate hardness?

A

The combination of chloride and sulfate hardness
(also known as permanent hardness)

23
Q

What is carbonate hardness typically equal to?

A

Alkalinity
(or the concentration of bicarbonate in mg/L as CaCO3)

24
Q

Give the range in mg/L as CaCO3 for the following degrees of hardness:
Soft
Moderately Hard
Hard
Very Hard

A

0-50
50-150
150-300
300+

25
Q

What is TOC?

A

Total Organic Carbon
(amount of organic matter)

26
Q

What are the 2 major sources of TOC in raw water?

A

Natural Organic Material (NOM)
Synthetic Organic Compounds (SOC)

27
Q

What are SOC’s?

A

1) Compounds formed through chemical reaction occurring during treatment (disinfectant byproduct or DBP like trihalomethanes)
2) Compounds originating from human activities

28
Q

Where do NOM’s originate from?

A

The degradation and end product of:
- plants and animal material
- microorganisms

29
Q

What are NOM’s?

A

Proteins
Carbohydrates
Lipids
Humic substances
Fluvic Substances

30
Q

What is a type of SOC formed in water treatment?

A

Disinfectant Byproduct (DBP)

31
Q

How are DBP’s formed?

A

The combination of disinfectants (chlorine) and natural organic material

32
Q

What are the two main groups of DBP’s?

A

THM’s and HAA’s
(Trihalomethanes and Haloacetic Acids)

Both of which are carcinogens

CIVL 7062 - Water Quality (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions