Question

= 41.856 ~41.9% Write the correct chemical names for the following compounds, all of which are either used or produced in this experiment. For each (except for NO2) state whether it is soluble or insoluble in water. Consult the solubility rules in the front of the lab manual or in the textbook. The first one has been completed as an example. Chemical Formula S = Soluble; I = Insoluble Name Cuo Copper(II)oxide HNO3 Cu(NO3)2 NO2 NaNO3 NaOH Cu(OH)2 H2S04 CuSO4 ZnSO4 Lab #8: The Copper Cycle

Answer 1

In the chemical name of a salt we write the cationic (positively charged) part first followed by the anionic (negatively charged) part.

We know that

a. All nitrates (salts witb NO₃^- ion) are soluble

b. Most sulphates (salts with SO₄^2-) are soluble (except BaSO₄, Ag₂SO₄, PbSO₄, SrSO₄, CaSO₄)

c. Most hydroxides are only slightly soluble. Hydroxides of group 1 elements are soluble whereas those of group II elements are slightly soluble. Hydroxides of transition elements are insoluble.

1.HNO₃

Chemical name: Nitric acid (it is a commonly known strong acid available in the laboratory)

We know that all nitrates are soluble in water. HNO₃ is a strong acid which is soluble in water.

2. Cu(NO₃)₂

Chemical name: Copper (II) nitrate (to balance the charge of two nitrate (NO₃^-) ions, Cu i.e. copper must be in +2 oxidation state thus the chemical name is as written above)

We know that all nitrates are soluble in water. Cu(NO₃)₂ is soluble in water.

3. NO₂

Chemical name: Nitrogen dioxide (there is a nitrogen N bonded to two oxygen O atoms hence the chemical name is as written above)

NO₂ gets hydrolysed in water i.e. it reacts with water.

5. NaNO₃

Chemical name: Sodium nitrate (Na⁺ is sodium ion and NO₃^- is nitrate ion and they balance each other's charge, thus the chemical name is as written above)

We know that all nitrates are soluble in water. NaNO₃ is soluble in water.

6. NaOH

Chemical name: Sodium hydroxide (Na⁺ is sodium ion and OH^- is hydroxide ion, they balance each other's charge, thus the chemical name is as written above)

NaOH (Hydroxide of group I element Na) is a strong base which is soluble in water.

7. Cu(OH)₂

Chemical name: Copper (II) hydroxide (To balance the negative charge of two hydroxide (OH^-) ions, there is a copper ion (Cu²⁺) in +2 oxidation state, thus the name is as written above)

Cu(OH)₂ (hydroxide of transition element Cu) is insoluble in water.

8. H₂SO₄

Chemical name: Sulphuric acid (A commonly known strong acid available in the laboratory)

H₂SO₄ is a strong acid which is soluble in water.

9. CuSO₄

Chemical name: Copper (II) sulphate (To balance the-2 charge of sulphate (SO₄^2-) ion copper (Cu²⁺) is in +2 oxidation state, thus the chemical name is as written above)

Most sulphates are soluble in water. CuSO₄ is soluble in water and forms a brilliant blue coloured solution.

10. ZnSO₄

Chemical name: Zinc sulphate (Zinc (Zn²⁺) ion balances the sulphate (SO₄^2-) ion, thus the name as written above)

ZnSO₄ is soluble in water and forms a colourless solution.