BGAS Grade 2/3 Model Multiple Choice question & answers - Part 2

-

26. Which metal corrode fast according to bimetallic principle?

a) Less electronegative

b) More Electropositive

c) More noble

d) Less Noble

 




27. Which one of the following is more noble?

a) Zinc

b) Steel

c) Millscale

d) Aluminium

 

28. The corrosion will takes place at

a) The Anode

b) The Cathode

c) The electrolyte 

d) Anode first than cathode

 

29. The by production of corrosion reaction is

a) Iron oxide

b) Iron sulphates

c) Iron chromate

d) Iron chloride

 

30. Aerobic condition would refer to?

a) Hydrogen

b) Oxygen

c) Nitrogen

d) Moisture

 

31. Which of the following is the highest known potential value?

a) Mill scale

b) Tin

c) Copper

d) Iron

 

32. The chemical composition of Hematite?

a) Fe2 O3

b) Oxygen

c) Nitrogen

d) Moisture

 

33. Which two materials are commonly used as sacrificial anodes?

a) Copper and Tungsten

b) Aluminium and Graphite

c) Zinc and Aluminium

d) Lead and Tin

 

34. Which of the following could be classified as a major cause of microbial corrosion?

a) Sulphur Eating Metal

b) Sulphur Reducing Bacteria

c) Rust inhibitive salts

d) Iron phosphates

 

35. Which is the more noble metal?

a) Steel

b) Aluminum

c) Magnesium

d) Tin

 

36. Which of the element will corrode quickly as per bimetallic principle?

a) Steel-Magnesium

b) Steel – Zinc

c) Steel - Aluminium

d) Carbon

 

37. Bi metallic corrosion causes

a) Causes a material of a higher nobility to corrode faster

b) Causes a material of the same nobility to corrode faster

c) Causes a material of lower nobility to corrode faster

d) Causes a material containing carbon to corrode faster

 

38. Molecular freedom of steel metal increases when

a) substrate contains salt

b) presence of oxygen

c) Temperature increases

d) Bacteria Affected

 

39. Which is more electropositive?

a) Silver

b) steel

c) mill scale

d) Magnesium

 

40. Mill scale is formed during steel rolling manufacturing operations in temperature at

a) Below 580  degree Celsius

b) Excess 580  degree Celsius

c) up to 580  degree Celsius

d) on 580 degree Celsius

 

41. Chemical name of rust

a) Hygroscopic salts

b) Hydrous iron oxide

c) mill scale

d) Hygroscopic blisters

 

42. Hygroscopic salts cause

a) Rash rusting

b) Pinholes

c) Rogue peak

d) Blisters

 

43. In the corrosion circuit, electron travel from

a) Anode to Cathode

b) Cathode to Anode

c) Electrolyte to both Cathode to Anode

d) None of the above

 

44. In the corrosion circuit, electron flow from

a) Anode to Cathode, via Electrolyte

b) Positive to Negative

c) Electrolyte to both Cathode to Anode

d) Anode to Cathode, via metallic path

 

45. In which salts would be found in Marine environment?

a) Potassium

b) Chloride

c) Sulphate

d) Zinc sulphate

 

46. In which salts would be found in Agricultural environment?

a) Sulphate

b) Potassium

c) Chloride

d) Potassium chloride

 

47. An Anode becomes positively charged by

a) Releasing proton to the cathode

b) Releasing electrons to the cathode

c) Receiving atoms from the cathode

d) None of the above

 

48. In the galvanic list, which of the following materials has the highest known potential values?

a) Mill scale

b) Copper

c) Al

d) Graphite

 

49. Steel becomes positively charged by

a) Releasing proton to the cathode

b) Releasing electrons to the cathode

c) Receiving atoms from the cathode

d) None of the above

 

50. In the galvanic list, which of the following materials has the lowest known potential values?

a) Mill scale

b) Copper

c) Aluminium

d) Graphite

 


Comments

Post a Comment

Popular posts from this blog

BGAS Grade 2/3 Model Multiple Choice question & answers - Part 3

-
Image
  51. Atom acquire the electric charged are a) Atomisation  b) Solaration c)  Polarisation d) Electromation   52. The British standard for preparation of steel substrate?  a) BS 3900  b) IGE SR 21  c)  BS 7079   d) ISO 8501    53. The two factors to consider when inspecting a surface preparation  a) Degree of cleanliness and time taken  b) Surface profile and material condition  c)  Surface profile and degree of cleanliness   d) Dependent upon the material thickness    54. Which is not a surface preparation cleaning methods in before paint application?  a) Dry abrasive blast cleaning  b) Hand and power tool leaning  c) Flame cleaning  d)  Light blast cleaning    55. Which pressure suitable for dry blasting?  a) 20psi  b)  100psi (Pounds per Square Inch)  (1 Psi = 6.89 kPa = 0.068 Bar) c) 220psi  d) 450psi    56. When using a Vent...
Read more

Holiday detection on Painted or Coated Surface

-
Holiday detection on Painted or Coated Surface A coating must be applied as a continuous film to perform its intended function. Early failure will occur if there is a discontinuity—a holiday, as it is commonly called—such as a pinhole, void, crack, thin spot, foreign inclusion, or contaminant in the coating film. Many of these defects are not readily visible, but they can be located using holiday detection equipment. Discontinuity: A void, crack, thin spot, foreign material inclusion, or contamination in the coating film that significantly lowers the electrical resistance of the coating. May also be identified as a holiday or pinhole. Holiday Defects characterized by a film having areas of insufficient thickness, even to the point where parts of the surface may remain uncoated. Holiday Detector: A device that locates discontinuities in a coating film applied to a conductive substrate. Pinhole The formation of minute hole in the wet film or drying due the burst of gases or...
Read more

BGAS Grade 2/3 Model Multiple Choice question & answers - Part 1

-
Image
1.  Corrosion is defined as : a) Rusting of Cathode b) Oxidation of iron in contact with water c)  Degradation of a material by chemical or electrochemical means d) Break down of metal by hydrogen   2. What is an electrolyte? a) It is a mixture of Salts and water b) A substance which will conduct electricity and cause rusting c) Oxidation liquid which will attack steel d)  A substance which will conduct a current and be broken down by it.   3. The degradation of material by chemical or electrochemical means is: a) Pickling followed by passivation b) Acid cleaning c)  Corrosion d) An Electrolyte   4. Is the electrical circuit in a corrosion reaction? a) AC b)  DC c) Negative charge d) Positive Charge   5. Hydrogen is evolved at a) The anode at all times b) The cathode at all times c)  The cathode as a by-product of the corrosion reaction d) The anode as corrosion takes place   6. Positively charged area  a)  Anode b) Cathod...
Read more