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 3 of 26.
Yashasvi said:
1 decade ago
Hydro sulphide is a colourless gas and if mixed with others, will get colourless.
ANAND SHARMA said:
1 decade ago
Actually brass constitutes of Cu+Zn, as it comes in contact of Hydrogen Sulphide, it transform into copper sluphate of blue color & zinc hydooxide of faint red color. Hence, it changes color.
Dev said:
1 decade ago
The Cu present in brass reacts with the sulphide ion of H2S forming CuS (cupric sulphide) which is black colored. Thus when brass is exposed to air it gets discolored.
Sushma said:
1 decade ago
I think B is the correct option Since the brass is an alloy of transition elements Zn and Cu,it reacts with hydrogen sulphide to get discolored
Paritosh said:
1 decade ago
What is hydrogen sulphide? why should we choose it ?
Hardik said:
1 decade ago
This process due to oxydation.
That's why I think answer is oxigen and oxigen must be present in process.
That's why I think answer is oxigen and oxigen must be present in process.
Jeeva said:
1 decade ago
The Cu present in brass reacts with the sulphide ion of H2S forming CuS (cupric sulphide) which is black colored. Thus when brass is exposed to air it gets discolored.
Rajdeep said:
1 decade ago
Give chemical reaction.
BHARAT said:
1 decade ago
Brass constitute zinc and copper and these two elements are transition elements. Among the given options hydrogen sulphide is more electronegative. So when it react with brass, brass get discolored.
Sahil Khare said:
1 decade ago
Hydrogen gas gives a smell of rotten eggs and turns lead acetate paper silvery back.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers