What is the ionic compound formula of potassium phosphate?


You can actually approach this question from two perspectives. You can

  • start from the name of the compound and try to understand why its chemical formula is written like that
  • start from the chemical formula and try to understand why the compound is named like that

So, let’s take the first approach. You know that the compound’s name is potassium phosphate. As you known, are always named cation first, followed by the anion.

Cations are ions that carry a positive charge and anions are ions that carry a negative charge.

So right from the start, you know that the cation must be the potassium cation, ##”K”^(+)##. This ion carries a ##1+## charge because potassium is a group 1 element.

This means that the anion must be the phosphate anion. Here is where a little knowledge of can prove to be very valuable.

The phosphate anion is actually a polyatomic ion made up of one phosphorus atom and four oxygen atoms. The chemical formula of the anion is ##”PO”_4^(3-)##.

Now, are always neutral. This means that you must balance the ##3-## charge on the anion by using three potassium cations.

The chemical formula of the compound will thus be

##3[“K”]^(color(red)(+)) [“PO”_4]^(color(blue)(3-)) <=> “K”_color(blue)(3)(“PO”_4)_color(red)(1) <=> color(green)(“K”_3″PO”_4)##

Now let’s take the second approach. You can identify the cation and the anion by taking apart the chemical formula of the compound.


As you know, ionic follow the criss cross rule, which states that the charge on the cation becomes the subscript of the anion, and vice versa.

Once again, it is very important to remember that cations are always written first!

So, you have

##”K”_color(blue)(3)”PO”_4 <=> “K”_color(blue)(3)(“PO”_4)_color(red)(1) <=> 3″K”^color(red)(+)”PO”_4^color(blue)(3-)##

So, the cation will carry a ##1+## charge, since you have ##”K”^(+)##. The anion will carry a ##3-## charge, since you have ##”PO”_4^(3-)##.

Once again, your cation will be the potassium cation and the anion will be the phosphate anion, hence the name potassium phosphate.

Calculate Your Essay Price
(550 words)

Approximate price: $22

Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
The price is based on these factors:
Academic level
Number of pages
Basic features
  • Free title page and bibliography
  • Unlimited revisions
  • Plagiarism-free guarantee
  • Money-back guarantee
  • 24/7 support
On-demand options
  • Writer’s samples
  • Part-by-part delivery
  • Overnight delivery
  • Copies of used sources
  • Expert Proofreading
Paper format
  • 275 words per page
  • 12 pt Arial/Times New Roman
  • Double line spacing
  • Any citation style (APA, MLA, Chicago/Turabian, Harvard)

Our guarantees

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.

Money-back guarantee

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 more

Zero-plagiarism guarantee

Each 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 more

Free-revision policy

Thanks 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 more

Privacy policy

Your 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 more

Fair-cooperation guarantee

By 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

Order your essay today and save 10% with the coupon code: best10