Question

fill in the name and empirical formula of each ionic compound that could be formed from the ions in this table:
some ionic compounds
cation | anion | empirical formula | name of compound
fe²⁺ | po₄³⁻ |
fe³⁺ | bro₃⁻ |
mg²⁺ | so₄²⁻ |

Explanation:

To solve for the empirical formulas and names of the ionic compounds, we use the principle of charge balance (the total positive charge equals the total negative charge in the compound).

First Row: $\boldsymbol{\ce{Fe^{2+}}}$ and $\boldsymbol{\ce{PO_4^{3-}}}$

Step 1: Determine the ratio of cations to anions

Let the number of $\ce{Fe^{2+}}$ ions be $x$ and $\ce{PO_4^{3-}}$ ions be $y$. The charge balance gives:
$$2x = 3y$$
The smallest integers satisfying this are $x = 3$ and $y = 2$ (since $2(3) = 3(2)$).

Step 2: Write the empirical formula

Using the ratio, the formula is $\ce{Fe_3(PO_4)_2}$.

Step 3: Name the compound

$\ce{Fe^{2+}}$ is iron(II), and $\ce{PO_4^{3-}}$ is phosphate. Thus, the name is iron(II) phosphate.

Second Row: $\boldsymbol{\ce{Fe^{3+}}}$ and $\boldsymbol{\ce{BrO_3^-}}$

Step 1: Determine the ratio of cations to anions

Let the number of $\ce{Fe^{3+}}$ ions be $x$ and $\ce{BrO_3^-}$ ions be $y$. The charge balance gives:
$$3x = 1y$$
The smallest integers satisfying this are $x = 1$ and $y = 3$.

Step 2: Write the empirical formula

Using the ratio, the formula is $\ce{Fe(BrO_3)_3}$.

Step 3: Name the compound

$\ce{Fe^{3+}}$ is iron(III), and $\ce{BrO_3^-}$ is bromate. Thus, the name is iron(III) bromate.

Third Row: $\boldsymbol{\ce{Mg^{2+}}}$ and $\boldsymbol{\ce{SO_4^{2-}}}$

Step 1: Determine the ratio of cations to anions

Let the number of $\ce{Mg^{2+}}$ ions be $x$ and $\ce{SO_4^{2-}}$ ions be $y$. The charge balance gives:
$$2x = 2y$$
The smallest integers satisfying this are $x = 1$ and $y = 1$.

Step 2: Write the empirical formula

Using the ratio, the formula is $\ce{MgSO_4}$.

Step 3: Name the compound

$\ce{Mg^{2+}}$ is magnesium, and $\ce{SO_4^{2-}}$ is sulfate. Thus, the name is magnesium sulfate.

Final Table

Cation	Anion	Empirical Formula	Name of Compound
$\ce{Fe^{3+}}$	$\ce{BrO_3^-}$	$\ce{Fe(BrO_3)_3}$	Iron(III) bromate
$\ce{Mg^{2+}}$	$\ce{SO_4^{2-}}$	$\ce{MgSO_4}$	Magnesium sulfate

Answer:

s (Row-wise):

1. Empirical formula: $\boldsymbol{\ce{Fe_3(PO_4)_2}}$; Name: $\boldsymbol{\text{iron(II) phosphate}}$
2. Empirical formula: $\boldsymbol{\ce{Fe(BrO_3)_3}}$; Name: $\boldsymbol{\text{iron(III) bromate}}$
3. Empirical formula: $\boldsymbol{\ce{MgSO_4}}$; Name: $\boldsymbol{\text{magnesium sulfate}}$