Question

1. Read Sections 5.1 -5.4 (pp. 159-187) and look at Table 5.1 (p. 172) in the textbook. Also, read Investigation 7. 2. In each box, write the formula for the substance described. Include physical states. copper metal copper(II) nitrate dissolved in water copper(II) sulfate dissolved in water 3 2 copper(II) hydroxide, solid state 3. Research, using the internet, to determine a reaction that will convert one substance into another for each step of the synthetic route described above. Write a balanced equation for each reaction, including physical states. 1. 2. 3.

Answer 1

Step-1

Copper reacts with nitric acid to give copper nitrate. The copper metal is oxidized by loosing two electrons and exists in 2+ state.

Cu (Solid) + 4 HNO₃ (liquid) $\rightarrow$ Cu(NO₃)₂ (aqueous solution) + 2H₂O (liquid) + 2 NO₂ (Gas)

Step 2

The reaction with aqueous sodium hydroxide gives rise to its corresponding hydroxide

Cu(NO₃)₂ (aqueous solution) + 2NaOH (aq )_{$\rightarrow$}Cu(OH)₂ (solid) + 2NaNO₃ (aqueous)

_Step-3

Cu(OH)2 undergoes dehydration leading to the formation of copper oxide with the elimination of water. The copper oxide thus formed reacts with sulphuric acid lead to the formation of Copper sulphate

Cu(OH)₂ (Solid)  $\rightarrow$ CuO (Solid) + H₂O (Liquid)

CuO (solid) + H₂SO4 (liquid) $\rightarrow$ Cu(SO₄)₂ (aqueous) + H₂O (liquid)

Step-4

Coppersulphate can be reduced to its metal state by redox reaction using Zn as follows

Cu(SO₄)₂ (aqueous)  + Zn (solid) $\rightarrow$ Cu (solid) + Zn(SO₄)₂ (aqueous)

This series of reactions begins and ends with copper metal. Since no copper is added or removed between Reactions step-1 to step-4, and since each reaction nearly goes to completion, you should be able to quantitatively recover all the copper metal you started with.