there are 2 reactants copper(II) oxide and hydrochloric acid the products are copper(II)chloride and water. what change will you observe in the copper(II)oxide? was there a change in solubility? where is the copper(II)chloride? how can you tell

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To determine the changes observed in copper(II) oxide when reacted with hydrochloric acid, as well as the solubility of the products and the location of copper(II) chloride, we can analyze the chemical equation and utilize some basic knowledge of chemistry.

The chemical equation for the reaction between copper(II) oxide (CuO) and hydrochloric acid (HCl) can be written as follows:

CuO + 2HCl → CuCl2 + H2O

1. Change observed in copper(II) oxide:
Copper(II) oxide is a solid, and when it reacts with hydrochloric acid, it will undergo a chemical reaction. The change observed in this case will be the disappearance or reduction in the amount of solid copper(II) oxide. The solid CuO will react with the hydrochloric acid, resulting in the formation of other products.

2. Change in solubility:
Copper(II) oxide is not soluble in water, hence its classification as a solid. However, after the reaction with hydrochloric acid, copper(II) chloride is formed as one of the products. Copper(II) chloride (CuCl2) is soluble in water, meaning it dissolves in water to form an aqueous solution. Therefore, there is a change in solubility from insoluble (CuO) to soluble (CuCl2).

3. Location of copper(II) chloride:
Since copper(II) chloride is soluble in water, it will exist in the form of an aqueous solution after the reaction. This means that the copper(II) chloride is present in the water portion of the reaction mixture.

4. How to tell the presence of copper(II) chloride:
One way to confirm the presence of copper(II) chloride is by performing a simple test called a "precipitation reaction." You can add a few drops of a reagent called sodium hydroxide (NaOH) to the reaction mixture. If copper(II) chloride is present, a blue precipitate, known as copper(II) hydroxide (Cu(OH)2), will form. This reaction is evidence of the presence of copper(II) ions, derived from copper(II) chloride.

In summary, when copper(II) oxide reacts with hydrochloric acid, the change observed is the disappearance or reduction in the amount of solid copper(II) oxide. This is accompanied by a change in solubility, as copper(II) chloride, one of the products, becomes soluble in water. The copper(II) chloride will exist in the water portion of the reaction mixture, and its presence can be confirmed by performing a precipitation reaction using sodium hydroxide.