Question

name

1. copper (ii) sulfide
2. copper (i) oxide
3. chromium (iii) sulfide
4. cobalt (ii) fluoride
5. iron (iii) nitride
6. lead (iv) iodide
7. silver (i) bromide
8. fecl₂
9. pb₃n₂
10. co₂s₃
11. cus
12. hg₂o
13. mncl₂
14. znf₂
15. what are some strategies that you are using to help you remember how to name correctly for transition metals and polyatomic ions?
16. what are some strategies that you are using to help you remember how to write formulas correctly for transition metals and polyatomic ions?

Explanation:

Step1: Identify transition - metal charge from name

For Copper (II) Sulfide, the Roman numeral (II) indicates the charge of copper is +2. The formula is formed by combining $Cu^{2 + }$ and $S^{2-}$ in a 1:1 ratio, so the formula is $CuS$.

Step2: For Copper (I) Oxide

The Roman numeral (I) shows copper has a +1 charge. Oxygen has a - 2 charge. To balance the charges, we need 2 copper ions for every 1 oxygen ion, so the formula is $Cu_2O$.

Step3: For Chromium (III) Sulfide

Chromium has a +3 charge. Sulfur has a -2 charge. To balance the charges, the least - common multiple of 3 and 2 is 6. So we need 2 chromium ions ($Cr^{3+}$) and 3 sulfur ions ($S^{2 - }$), and the formula is $Cr_2S_3$.

Step4: For Cobalt (II) Fluoride

Cobalt has a +2 charge and fluorine has a -1 charge. We need 2 fluorine ions for every 1 cobalt ion, so the formula is $CoF_2$.

Step5: For Iron (III) Nitride

Iron has a +3 charge and nitrogen has a -3 charge. The formula is $FeN$.

Step6: For Lead (IV) Iodide

Lead has a +4 charge and iodine has a -1 charge. We need 4 iodine ions for every 1 lead ion, so the formula is $PbI_4$.

Step7: For Silver (I) Bromide

Silver has a +1 charge and bromine has a -1 charge. The formula is $AgBr$.

Step8: For $FeCl_2$

Chlorine has a -1 charge. Since there are 2 chlorine atoms, the total negative charge is -2. So iron has a +2 charge, and the name is Iron (II) Chloride.

Step9: For $Pb_3N_2$

Nitrogen has a -3 charge. The total negative charge from 2 nitrogen atoms is -6. Since there are 3 lead atoms, each lead atom has a +2 charge, and the name is Lead (II) Nitride.

Step10: For $Co_2S_3$

Sulfur has a -2 charge. The total negative charge from 3 sulfur atoms is -6. Since there are 2 cobalt atoms, each cobalt atom has a +3 charge, and the name is Cobalt (III) Sulfide.

Step11: For $CuS$

Sulfur has a -2 charge, so copper has a +2 charge, and the name is Copper (II) Sulfide.

Step12: For $Hg_2O$

Oxygen has a -2 charge. Since there are 2 mercury atoms, each mercury atom has a +1 charge, and the name is Mercury (I) Oxide.

Step13: For $MnCl_2$

Chlorine has a -1 charge. Since there are 2 chlorine atoms, the total negative charge is -2. So manganese has a +2 charge, and the name is Manganese (II) Chloride.

Step14: For $ZnF_2$

Zinc is not a transition metal in the strict - sense of variable oxidation states like the others in this context. But if we consider it, fluorine has a -1 charge. Since there are 2 fluorine atoms, zinc has a +2 charge, and the name is Zinc (II) Fluoride.

| Name | Transition Metal Charge | Formula |
|---|---|---|
| 1. Copper (II) Sulfide | +2 | $CuS$ |
| 2. Copper (I) Oxide | +1 | $Cu_2O$ |
| 3. Chromium (III) Sulfide | +3 | $Cr_2S_3$ |
| 4. Cobalt (II) Fluoride | +2 | $CoF_2$ |
| 5. Iron (III) Nitride | +3 | $FeN$ |
| 6. Lead (IV) Iodide | +4 | $PbI_4$ |
| 7. Silver (I) Bromide | +1 | $AgBr$ |
| 8. Iron (II) Chloride | +2 | $FeCl_2$ |
| 9. Lead (II) Nitride | +2 | $Pb_3N_2$ |
| 10. Cobalt (III) Sulfide | +3 | $Co_2S_3$ |
| 11. Copper (II) Sulfide | +2 | $CuS$ |
| 12. Mercury (I) Oxide | +1 | $Hg_2O$ |
| 13. Manganese (II) Chloride | +2 | $MnCl_2$ |
| 14. Zinc (II) Fluoride | +2 | $ZnF_2$ |

For question 15:
Some strategies to remember naming and formula - writing for transition metals and polyatomic ions:
- **Memorize Roman numerals**: Associate the Roman numerals with the charge of the transition metal in the name. For example, (I) is +1, (II) is +2, (III) is +3, etc.
- **Use charge - balancing rules**: For formula - writing, remember the charges of common non - metals and polyatomic ions. Then balance the charges of the transition metal and the non - metal or polyatomic ion to get the correct formula.
- **Practice with flashcards**: Write the name on one side of a flashcard and the formula and charge on the other side and practice regularly.

Answer:

Name	Transition Metal Charge	Formula
2. Copper (I) Oxide	+1	$Cu_2O$
3. Chromium (III) Sulfide	+3	$Cr_2S_3$
4. Cobalt (II) Fluoride	+2	$CoF_2$
5. Iron (III) Nitride	+3	$FeN$
6. Lead (IV) Iodide	+4	$PbI_4$
7. Silver (I) Bromide	+1	$AgBr$
8. Iron (II) Chloride	+2	$FeCl_2$
9. Lead (II) Nitride	+2	$Pb_3N_2$
10. Cobalt (III) Sulfide	+3	$Co_2S_3$
11. Copper (II) Sulfide	+2	$CuS$
12. Mercury (I) Oxide	+1	$Hg_2O$
13. Manganese (II) Chloride	+2	$MnCl_2$
14. Zinc (II) Fluoride	+2	$ZnF_2$

1. Strategies include memorizing Roman numerals, using charge - balancing rules, and practicing with flashcards.