If you had left your copper(II) nitrate/potassium hydroxide precipitate stand for a while, the precipitate would turn into a black powder. The copper doesn’t reduce in this reaction, but one mole of water is produced from the reaction of one mole of the copper precipitate. Predict the product of this decomposition reaction.
The ppt is Cu(OH)2.
So Cu(OH)2 ==> black? + H2O
Since the problem tells you there is no oxidation/reduction, just take out the water and see what's left. And you should know CuO is black.
Cu(OH)2 ==> CuO)(black) + H2O
Well, if I had to take a guess, I would say that the product of this decomposition reaction might be... drumroll, please... a magic trick!
Yes, that's right! When you leave your copper(II) nitrate/potassium hydroxide precipitate to stand for a while, the black powder that forms could actually transform into a magical puff of smoke! It's like turning science into a circus act!
But in all seriousness, the actual product of this decomposition reaction is copper(II) oxide (CuO). So, no magic tricks this time, but hey, copper(II) oxide is pretty cool too!
The decomposition of copper(II) hydroxide (formed from the reaction between copper(II) nitrate and potassium hydroxide) can be represented by the equation:
Cu(OH)2 → CuO + H2O
In this reaction, copper(II) hydroxide decomposes into copper(II) oxide and water. Therefore, the product of this decomposition reaction is copper(II) oxide (CuO) and water (H2O).
To predict the product of a decomposition reaction, we need to consider the reactants and the conditions under which the reaction takes place.
In this case, the reaction involves the decomposition of the copper(II) nitrate/potassium hydroxide precipitate. The formation of a black powder suggests that a chemical change has occurred, which could involve a change in the oxidation state of the copper ions.
When copper(II) nitrate and potassium hydroxide react, they form a precipitate of copper(II) hydroxide and soluble potassium nitrate:
Cu(NO3)2 + 2KOH → Cu(OH)2 + 2KNO3
However, if the precipitate is allowed to stand for a while, it can undergo further changes. One possibility is that the copper(II) hydroxide decomposes to form copper(II) oxide (CuO) and water (H2O):
Cu(OH)2 → CuO + H2O
Since the reaction indicates that one mole of water is produced from the reaction of one mole of the copper precipitate, it suggests that the decomposition proceeds as follows:
2Cu(OH)2 → 2CuO + 2H2O
Therefore, the predicted product of this decomposition reaction is copper(II) oxide (CuO), a black powder, and water (H2O).