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POST YOUR BIO AND CHEM PAPER 1 DOUBT HERE !!!!

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Which products are formed when magnesium reacts with steam?
A magnesium hydroxide and hydrogen
B magnesium hydroxide and oxygen
C magnesium oxide and hydrogen
. 0 magnesium oxide and oxygen
why it is A not C
because thats just it. You have to know wen metals like sodium, potassium and calcium react with cold water a hydroxide plus hydrogen gas is formed. Magnesium and metals down cant react with cold water but instead steam to give an oxide and hydrogen
 
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yes but boiling and melting is right I believe ???? I have a silly question to you which change was exothermic L--> g or g ---->L ???
g-->L was exothermic
and yeah u're right B.p and M.P can be right but remember to check to purity of:
liquids-boiling point
solid- melting point
for aqueous mixtures: Chromatopraphy
 
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aiaiayay i frgot the question abt the coffee beans one ..i do hope chromatography is also right cuz i wrote that.
 
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g-->L was exothermic
and yeah u're right B.p and M.P can be right but remember to check to purity of:
liquids-boiling point
solid- melting point
for aqueous mixtures: Chromatopraphy
Thanks , what about for how acid rain is formed? What did you right ? Also for chlorobutane what was the isomers last questions ? ???!
 
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Thanks , what about for how acid rain is formed? What did you right ? Also for chlorobutane what was the isomers last questions ? ???!
for the acid rain I wrote how sulphurdioxide is mixed with rain water in the atmosphere and for the Isomers I made one 1cholrobutane and the other 2cholrobutane
 
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Please explain this answer.. super confused!

MLHv8.jpg
 
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The Chromium did not lose any electron or gained it , and Because KOH is alkali is basic so it will increase the pH , I believe so !!!
 
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Please explain this answer.. super confused!

MLHv8.jpg
thinking about this logically .. we have water at the end therefore the solution becomes less acidic .. which means the pH increases​
the oxidation state of chromium stays 6+ ... as in the ionic eqn : 2CrO4 ^-2 + 2H+ ----> Cr2O7^2- + H2O .. hope u got it :D
 
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thinking about this logically .. we have water at the end therefore the solution becomes less acidic .. which means the pH increases​
the oxidation state of chromium stays 6+ ... as in the ionic eqn : 2CrO4 ^-2 + 2H+ ----> Cr2O7^2- + H2O .. hope u got it :D
Not being mean or so…But the reason behind the increase in pH is that the alkali was in excess…There was questio asking wat would neutralize HCl there was water and ammonia,the answer was ammonia…So adding water and changing the dilution and concentration can't move a reagent from an acidic to neutral state since you r adding H ions :)
 
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Not being mean or so…But the reason behind the increase in pH is that the alkali was in excess…There was questio asking wat would neutralize HCl there was water and ammonia,the answer was ammonia…So adding water and changing the dilution and concentration can't move a reagent from an acidic to neutral state since you r adding H ions :)
i have bad logic :p ... thx for clarifying (at least if something similar came ill know how to answer right) :D
 
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guys just a quick question for chem 31 the question abt the oxidant needed for ethanol ---> ethanoic acid conversion it cud be potassium manganate or dichromate. Was it necessary to mention the oxidation number?
 
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