##”Cr”_2″O”_3##
The first thing to notice here is that you’re dealing with an ionic compound that contains chromium, ##”Cr”##, a transition metal, and oxygen, ##”O”##, a non-metal.
The interesting thing about this compound is that it contains a transition metal as its cation, i.e. its positively charged ion. As you know, the name of a transition metal cation is written using Roman numerals.
This is done to distinguish between the possible oxidation states that transition metals can exhibit. In this case, the name of the compound contains the (III) Roman numeral, which implies that the metal has a ##+3## oxidation state.
In other words, the cation carries a ##color(blue)(3+)## positive charge
##”Cr”^color(blue)((3+)) ->## the chromium(III) cation
The anion, i.e. the negatively charged ion, is written using the -ide prefix. In this case, you’re dealing with the oxide anion, ##”O”^color(red)(2-)##.
The anion carries a ##color(red)(2-)## charge because oxygen is located in group 16 of , and thus requires two more electrons in its outermost shell to complete its octet.
##”O”^color(red)(2-) ->## the oxide anion
Now, an ionic compound must be electrically neutral, which implies that the total positive charge coming from the cation must be balanced by the total negative charge coming from the anion.
In this case, you need ##color(red)(2)## chromium(III) cations and ##color(blue)(3)## oxide anions in order to have a neutral compound.
##color(red)(2) xx [“Cr”^color(blue)(3+)] + color(blue)(3) xx [“O”^color(red)(2-)] -> “Cr”_ color(red)(2)”O”_ color(blue)(3)##
The chemical formula for chromium(III) oxide will thus be
##color(green)(|bar(ul(color(white)(a/a)color(black)(“Cr”_2″O”_3)color(white)(a/a)|)))##
Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.
You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.
Read moreEach paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.
Read moreThanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.
Read moreYour email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.
Read moreBy sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.
Read more