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Author: Subject: A long and hard quest, can anyone help me?
namnguyenvn2904
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sad.gif posted on 28-7-2019 at 00:15
A long and hard quest, can anyone help me?


Some students went to the lab to experiment the reaction speed, but unintentionally, when they finished, they forgot to cover the lid of a bottle of chemical A which has the label " preserve in dark place ”. After a while, the teachers conducted the lab and discovered that the chemicals in the bottle A were transformed into three new compounds, B, C and D. Compound A can be used to increase the dissolution of compound C in aqueous solutions by forming D. If mixing concentrated solutions of A and B together then reacting with a greenish yellow F gas will produce two salt G and H in acid environment. Salt G reacts with A to form a dull brown solution containing C. Oxygen accounts for 22.4% by weight of G. F gas reacts with hydrogen under lighting conditions to produce J. acid. G react with J to form C, F and H. Find the possible formula of A,B,C,D,F,G,H,J
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j_sum1
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Mood: Metastable, and that's good enough.

[*] posted on 28-7-2019 at 00:47


Let's see if I got this right.
You want someone to help with your homework...

Let us know what you have figured out so far, what you have been studying and where you got stuck. Then someone will help you over the bump.




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namnguyenvn2904
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[*] posted on 28-7-2019 at 02:51


I am doubting whether A can be KI, NaI, KMnO4 but B,C,D make me confused because i have never learnt about the decomposition of A in light or even effected by air, water. More than, Why A can increase dissolution of C :/
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Pumukli
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[*] posted on 28-7-2019 at 04:07


As j_sum1 said: "let us know what what you have been studying"!

What can be the F gas which reacts with hydrogen under lighting and has greenish yellow color? There aren't many coloured gases...

What can be in the dull brown solution (C), which dissolution can be increased if mixed with something (A)? There aren't many compounds which are 1, brown in water and 2, their dissolution can be increased by adding something...

F gas reacts with something and the result contains 22.4% O. Do you know how to calculate the elemental % composition of a compound?

So the question is: what do you know and what are you studying?

Hint: KMnO4 solution is either pink/purple (diluted) or blackish (when concentrated). Never dull brown.

[Edited on 28-7-2019 by Pumukli]
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namnguyenvn2904
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[*] posted on 28-7-2019 at 04:14


Yes i know what i am studying. F is Cl2 and J is HCl, i know these already. This kind of exercise is very common in Vietnam. I need to apply all knowledge i know. I can find the substance because maybe my knowledge is limited. Therefore i need your guy help. If a dull brown solution i often think about I2 solution.
What do you guy think
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AJKOER
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[*] posted on 28-7-2019 at 04:43


Yes, brown solution I2, or I3- in the presence of I-. and its salts iodides are general light sensitive, especially AgI.
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