Chapter 2

Question 1

a complex phenomena that may involve one or more forms

Answer 1

corrosion

Question 2

corrosion of metals, confined to the metal surface but sometimes along grain boundaries

Answer 2

chemical or electrical corrosion

Question 3

is the deterioration of plastics and other nonmetals resulting in swelling, crazing, cracking, softening, and/or decomposition

Answer 3

physiochemical corrosion

Question 4

initiated by galvanic action

Answer 4

corrosive action

Question 5

an electrical potential can be set operating between two series of various metals

Answer 5

galvanic corrosion

Question 6

corrosion rate of most metals is affected by __

Answer 6

pH

Question 7

they are powerful accelerators of corrosion

Answer 7

oxidizing agents

Question 8

____ tend to increase with rising temperature

alos thend to increased with an increase in the volume

Answer 8

rate of corrosion

Question 9

involves gray cast iron in which the metals converted to graphite’s mixed with iron corrosion products.

Answer 9

graphitic corrosion

Question 10

corrosion of brass alloy containing Zn in which the principal product of corrosion is metallic copper

Answer 10

dezincification

Question 11

metabolic activity of microorganisms can either directly or indirectly cause deterioration of a metal by corrosion processes

Answer 11

biological corrosion

Question 12

___ activity in the fluid can produce corrosive environment

Answer 12

biological activity

Question 13

Microorganisms associated with corrosion are either

*___ - thrive in the presence of oxygen
*___ - thrive in the absence of oxygen

Answer 13

aerobic, anaerobic

Question 14

how to combat corrosion

• change in the ___ environment
• use of an ___
• ___ protection
• ___ of corrosive metals
• use of ___ material in the design

Answer 14

*operating
*inhibitor
*cathodic/anodic
*substitution
*permissible

Question 15

2 general classification of metals

Answer 15

metals and nonmetals

Question 16

AISI

Answer 16

American Iron and Steel Institute

Question 17

what is the most commonly used material for chemical process industries

Answer 17

ferrous metals/alloy carbon steel

Question 18

this material contains one or more alloying components to improve the its chemical and corrosive resistance

Answer 18

low-alloy steel

Question 19

increases toughness and improves low temperature properties and corrosion resistance

Answer 19

nickel

Question 20

improves hardness/abrasion resistance, corrosion resistance to oxidation

Answer 20

chromium and silicon

Question 21

_ provides added strength for higher temperature operation

Answer 21

MOLYBDENUM

Question 22

contain 12-20% Chromium with controlled amount of Carbon and other alloys.

Answer 22

Martensic alloys

Question 23

SS contain 15-30% Chromium with 0.1% or less Carbon content

Answer 23

Ferritic

Question 24

_ SS most corrosive resistant among the 3, contain 16-26%Chromium and 6-22% nickel

Answer 24

Austinistic

Question 25

exhibits **high corrosion resistance** to most *alkaline*

Answer 25

nickel

Question 26

_ used extensively for equipment in caustic soda producing **alkaline production**

Answer 26

Nickel clad Steel

Question 27

67% nickel and 30% copper; used in **food** industries

Answer 27

monel

Question 28

**77% nickel** and 15% chromium

Answer 28

inconel

Question 29

* **Light and easy** to fabricate * **Resists attacks by acid** because of surface film * Lower corrosion resistance than pure metal * Metallic Mercury, heavy metals ions or chloride ions can cause rapid failure

Answer 29

aluminum and its alloys

Question 30

Metallic Mercury, heavy metals ions or chloride ions can cause ___

Answer 30

rapid failure

Question 31

* Relatively **inexpensive** * Possesses **fair mechanical strength** * Can be **fabricated easily** into different shapes * Readily **susceptible to oxidation** * **Resistant to atmospheric, moisture**, oxygen because a protective coating Of copper oxide is found on the surface.

Answer 31

copper and its alloys

Question 32

* has **low creep and fatigue resistance** * good resistance to sulphuric and phosphoric acid

Answer 32

lead and alloys

Question 33

* physical properties s**imilar to mild steel** with the exception of its melting point (2996 deg C) * Highly strong with with medium weight educing medium * **Corrosion resistance is superior** in oxidizing and acid E * Excellent **resistant to seawater** * Resistant to nitric acid except with fuming nitric * Resistant to ferric chloride and other hot chlorides

Answer 33

Tantalum

Question 34

* Has **excellent resistance to reducing environment** * Oxidizing agent caused accelerated attack * **Resists all chlorides except ferric and cupric** * Damaged by sulphuric acid above 70%

Answer 34

zirconium

Question 35

include glass, stoneware, brick, cement have **low structural strength**

Answer 35

inorganic nonmetals

Question 36

limited to relatively **moderate temperature and pressure** such as plastics, rubber, wood, carbon

Answer 36

organic nonmetals

Question 37

account for a **large fraction of the purchased cost** of equipment

Answer 37

fabrication expenses