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Physics, Chemistry and Biology: Post your doubts here!

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An excess of copper oxide is added to the acid, meaning that the salt is added in such quantities that no more of the salt can dissolve in it anymore i.e the acid has become saturated.
im sorry i dont understand :confused:
 

Maz

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any one :/ :/
10) small tip about balancing - always keep the balancing of oxygen and hydrogen for the last.
13) you have to know the electrolysis of molten lead bromide.
14) Since both of them are positive.
15) sorry.
16) Using fuels is always exothermic and hydrogen is oxidised to H2O, uranium only emits radiation which is used, it is not oxidised.
 
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10) small tip about balancing - always keep the balancing of oxygen and hydrogen for the last.
13) you have to know the electrolysis of molten lead bromide.
14) Since both of them are positive.
15) sorry.
16) Using fuels is always exothermic and hydrogen is oxidised to H2O, uranium only emits radiation which is used, it is not oxidised.
and also 17) copper oxide always forms copper after heating
18) the most reactive is never reduced :)
 
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10) small tip about balancing - always keep the balancing of oxygen and hydrogen for the last.
13) you have to know the electrolysis of molten lead bromide.
14) Since both of them are positive.
15) sorry.
16) Using fuels is always exothermic and hydrogen is oxidised to H2O, uranium only emits radiation which is used, it is not oxidised.
thank uuuu
 
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Can anyone help me?
An excess of copper(II) oxide is added to dilute sulfuric acid to make crystals of hydrated
copper(II) sulfate.
The processes listed may be used to obtain crystals of hydrated copper(II) sulfate.
1 concentrate the resulting solution
2 filter
3 heat the crystals
4 wash the crystals
Which processes are needed and in which order?
A 1, 2, 3 and 4
B 1, 2, 4 and 3
C 2, 1, 2 and 3
D 2, 1, 2 and 4
i know that the answer is D because 3 should NOT be involved , but other than that.. could some1 explain?
 

Maz

Messages
302
Reaction score
665
Points
103
Can anyone help me?
An excess of copper(II) oxide is added to dilute sulfuric acid to make crystals of hydrated
copper(II) sulfate.
The processes listed may be used to obtain crystals of hydrated copper(II) sulfate.
1 concentrate the resulting solution
2 filter
3 heat the crystals
4 wash the crystals
Which processes are needed and in which order?
A 1, 2, 3 and 4
B 1, 2, 4 and 3
C 2, 1, 2 and 3
D 2, 1, 2 and 4
i know that the answer is D because 3 should NOT be involved , but other than that.. could some1 explain?
That itself disqualifies all the other 3 options.
Other than that, (A & B) , why should one concentrate an already saturated solution for crystallization?
 
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