General Knowledge - General Science - Discussion
Discussion Forum : General Science - Elements and Metals (Q.No. 1)
1.
Brass gets discoloured in air because of the presence of which of the following gases in air?
Discussion:
254 comments Page 17 of 26.
Science genius said:
1 decade ago
Oxygen makes metal corrode, so I think A might be a right answer too.
Scholar said:
1 decade ago
In most of the answers it is said that sulphur reacts with brass but it cannot be ignored that hydrogen sulphide is a compound sulphur not only can react with brass.
Physic said:
1 decade ago
When object is place between focus and optical center.
Priya said:
1 decade ago
Option b is the answer because it removes the chlorophyll from plants.
Nirmaljeet kaur said:
1 decade ago
It is due to oxygen so the answer is A.
Satyendra pal said:
1 decade ago
Option is A because oxygen gas is present in air.
Mitu moharana said:
1 decade ago
Its due to sulphide only.
Upender said:
1 decade ago
The normal brown coloration on brass which slowly forms is primarily due to the oxidation of the copper (which makes up about 70% or more of the Brass alloy) to copper oxide.
The greenish patina that forms on brass (especially in inclement environments) can be a complex of copper carbonates and acetates (acetates come from naturally or artificially occurring contaminants or droppings in the atmosphere depending on the presence of Industry).
Vinegar (acetic acid) is capable of producing an intense green corrosion on brass (copper acetate) and copper alloys generally. Regions near industry may be exposed to Sulfur compounds such as Sulfur Dioxide, or Hydrogen Sulfide.
The greenish patina that forms on brass (especially in inclement environments) can be a complex of copper carbonates and acetates (acetates come from naturally or artificially occurring contaminants or droppings in the atmosphere depending on the presence of Industry).
Vinegar (acetic acid) is capable of producing an intense green corrosion on brass (copper acetate) and copper alloys generally. Regions near industry may be exposed to Sulfur compounds such as Sulfur Dioxide, or Hydrogen Sulfide.
Anu said:
1 decade ago
Yes it is as hydrogen sulphide clears the chlorophyll from the sensitive plants and plants which are found in hilly regions.
Sandeep singh said:
1 decade ago
Hydrogen sulphide is (sulphur and oh-) so it is base and there is ph value is more than 7 so it is react with brass presence of air and discoloured the brass so hydrogen sulphide is right answer.
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