Question

determine the chemical formula of the ionic compounds listed below with transition metals: 1. manganese (iv) oxide 2. lead (ii) oxide 3. cobalt (ii) chloride 4. iron (iii) sulfide 5. iron (ii) oxide

Explanation:

Step1: Recall ion - charge and element symbols

Manganese(IV) has a charge of + 4, and oxygen has a charge of - 2. The symbol for manganese is Mn and for oxygen is O.

Step2: Use criss - cross method

To form a neutral compound, we use the criss - cross method. We take the absolute value of the charges and swap them as subscripts. So for Mn$^{4 + }$ and O$^{2 - }$, the formula is MnO$_2$.

Step3: For lead(II) oxide

Lead(II) has a charge of + 2, and oxygen has a charge of - 2. The symbol for lead is Pb and for oxygen is O. Using the criss - cross method, the formula is PbO.

Step4: For cobalt(II) chloride

Cobalt(II) has a charge of + 2, and chloride (from chlorine) has a charge of - 1. The symbol for cobalt is Co and for chlorine is Cl. Using the criss - cross method, the formula is CoCl$_2$.

Step5: For iron(III) sulfide

Iron(III) has a charge of + 3, and sulfide (from sulfur) has a charge of - 2. The symbol for iron is Fe and for sulfur is S. Using the criss - cross method, the formula is Fe$_2$S$_3$.

Step6: For iron(II) oxide

Iron(II) has a charge of + 2, and oxygen has a charge of - 2. The symbol for iron is Fe and for oxygen is O. Using the criss - cross method, the formula is FeO.

Answer:

1. MnO$_2$
2. PbO
3. CoCl$_2$
4. Fe$_2$S$_3$
5. FeO