What is the formula for copper(II) chloride?

A. [tex]$ClCu _2$[/tex]
B. [tex]$CuCl _2$[/tex]
C. [tex][tex]$Cu _2 Cl _2$[/tex][/tex]
D. [tex]$Cu _2 Cl$[/tex]



Answer :

Let's determine the correct chemical formula for copper(II) chloride step by step.

1. Identify the ions involved:
- Copper(II) means copper with a +2 charge. We denote this as [tex]\( \text{Cu}^{2+} \)[/tex].
- Chloride is the anion formed by chlorine and it has a -1 charge. We denote this as [tex]\( \text{Cl}^- \)[/tex].

2. Determine the ratio of the ions to balance the charge:
- Since copper(II) has a +2 charge, we need enough chloride ions to balance this positive charge.
- Each chloride ion has a -1 charge. Therefore, to balance the +2 charge of one copper ion, we need two chloride ions.

3. Combine the ions to form the compound:
- For each [tex]\( \text{Cu}^{2+} \)[/tex], you need two [tex]\( \text{Cl}^- \)[/tex] to balance the charges.

4. Write the chemical formula:
- Place the symbols together and use subscripts to indicate the number of ions. Thus, one copper ion pairs with two chloride ions to form [tex]\( \text{CuCl}_2 \)[/tex].

Now, let's review the given options:

- [tex]\( \text{ClCu}_2 \)[/tex]: This format does not reflect the correct ion ratio and ordering.
- [tex]\( \text{Cu}_2 \text{Cl}_2 \)[/tex]: This suggests two copper atoms and two chloride atoms, which would actually correspond to a different compound, not copper(II) chloride.
- [tex]\( \text{Cu}_2 \text{Cl} \)[/tex]: This suggests two copper atoms with one chloride atom, which is incorrect.
- [tex]\( \text{CuCl}_2 \)[/tex]: This correctly suggests one copper ion with two chloride ions, balancing the charges correctly.

Therefore, the correct formula for copper(II) chloride is [tex]\( \text{CuCl}_2 \)[/tex].