Question

formula:
name: cobalt (iii) fluoride

formula:
name: carbon disulfide

formula:
name: potassium sulfide

formula: ch₄
name:

Explanation:

For Cobalt (III) fluoride:

Step1: Determine oxidation states

Cobalt (III) has a charge of \( +3 \) (\( \text{Co}^{3+} \)), fluoride has a charge of \( -1 \) (\( \text{F}^- \)).

Step2: Balance charges

To balance the charges, we need 3 fluoride ions for each cobalt (III) ion. So the formula is \( \text{CoF}_3 \).

For Carbon disulfide:

Step1: Identify elements and prefixes

Carbon (C) and sulfur (S). The prefix "di-" for sulfur means 2 sulfur atoms.

Step2: Write the formula

So the formula is \( \text{CS}_2 \).

For Potassium sulfide:

Step1: Determine oxidation states

Potassium (K) has a charge of \( +1 \) (\( \text{K}^+ \)), sulfide (S) has a charge of \( -2 \) (\( \text{S}^{2-} \)).

Step2: Balance charges

We need 2 potassium ions for each sulfide ion. So the formula is \( \text{K}_2\text{S} \).

For \( \text{CH}_4 \):

Answer:

s:

• Cobalt (III) fluoride: \( \text{CoF}_3 \)
• Carbon disulfide: \( \text{CS}_2 \)
• Potassium sulfide: \( \text{K}_2\text{S} \)
• \( \text{CH}_4 \): Methane