Write the name of each compound by the Stock System (IUPAC)
ZnSO4
CuCO3
Cd(NO3)2
FeS
Cr(ClO3)3
The correct answer and explanation is :
Here are the names of the compounds in the Stock System (IUPAC):
- ZnSO₄: Zinc sulfate
- CuCO₃: Copper(II) carbonate
- Cd(NO₃)₂: Cadmium nitrate
- FeS: Iron(II) sulfide
- Cr(ClO₃)₃: Chromium(III) chlorate
Explanation:
The Stock System is a way to name compounds, especially those containing transition metals that can have more than one possible oxidation state. The main feature of the Stock System is that it includes the oxidation state of the metal in parentheses as a Roman numeral. Let’s go through each compound:
- ZnSO₄ (Zinc sulfate):
- Zinc (Zn) is a transition metal that only has one common oxidation state, +2. Thus, there is no need to specify the oxidation state in the name. The compound is called zinc sulfate, where sulfate (SO₄²⁻) is the polyatomic anion.
- CuCO₃ (Copper(II) carbonate):
- Copper (Cu) can have two oxidation states: +1 and +2. In CuCO₃, copper has an oxidation state of +2 (since carbonate, CO₃²⁻, has a charge of -2). Therefore, the compound is named copper(II) carbonate.
- Cd(NO₃)₂ (Cadmium nitrate):
- Cadmium (Cd) always has an oxidation state of +2 in its compounds. Since there is only one common oxidation state, there’s no need to specify it. Therefore, the compound is called cadmium nitrate.
- FeS (Iron(II) sulfide):
- Iron (Fe) can have multiple oxidation states, but in FeS, iron has an oxidation state of +2 (since sulfide, S²⁻, has a charge of -2). Hence, the name is iron(II) sulfide.
- Cr(ClO₃)₃ (Chromium(III) chlorate):
- Chromium (Cr) can have several oxidation states, but in Cr(ClO₃)₃, chromium has an oxidation state of +3. Therefore, the name of the compound is chromium(III) chlorate.
The Stock System is useful for distinguishing between compounds that involve metals that can have multiple oxidation states, especially transition metals, to avoid confusion.