The iron in the compound has a charge of [tex]$Fe^{+2}$[/tex]. What is the formula of iron(II) chromate? chromate ion: [tex]$(CrO_4)^{-2}$[/tex]
A. [tex]$FeCr_2O_7$[/tex]
B. [tex]$FeCrO_4$[/tex]
C. [tex]$Fe(CrO_4)_2$[/tex]
D. [tex]$Fe_2CrO_4$[/tex]
Answer (1)
The iron(II) ion has a charge of +2: F e + 2 .
The chromate ion has a charge of -2: ( C r O 4 ) − 2 .
They combine in a 1:1 ratio to form a neutral compound.
The formula of iron(II) chromate is F e C r O 4 .
Explanation
Understanding the Problem We are given that the iron ion has a charge of +2, denoted as F e + 2 , and the chromate ion has a charge of -2, denoted as ( C r O 4 ) − 2 . Our goal is to determine the chemical formula of iron(II) chromate.
Determining the Ratio Since the iron(II) ion has a +2 charge and the chromate ion has a -2 charge, they will combine in a 1:1 ratio to form a neutral compound. This means that one iron(II) ion will combine with one chromate ion.
The Chemical Formula Therefore, the chemical formula of iron(II) chromate is F e C r O 4 .
Examples
In chemistry, understanding how ions combine to form neutral compounds is crucial. For instance, in environmental science, knowing the formula of iron(II) chromate helps in predicting its behavior in water and soil. This knowledge is essential for assessing potential environmental risks and developing remediation strategies. Similarly, in materials science, the formula guides the synthesis of new materials with specific properties. For example, iron(II) chromate can be used as a pigment or a catalyst, and its formula ensures the correct stoichiometry during its production.
