What is the Difference Between Potassium Chloride and Potassium Phosphate

The key difference between potassium chloride and potassium phosphate is that potassium chloride has a chloride anion bound to potassium cation, whereas potassium phosphate has one, two, or three phosphate anions bound to potassium cation.

Potassium chloride is an inorganic compound having the chemical formula KCl. Potassium phosphate, on the other hand, is a generic name used for salts of potassium and phosphate ions, which include monopotassium phosphate, dipotassium phosphate, and tripotassium phosphate.

CONTENTS

1. Overview and Key Difference
2. What is Potassium Chloride 
3. What is Potassium Phosphate
4. Potassium Chloride vs Potassium Phosphate in Tabular Form
5. Summary – Potassium Chloride vs Potassium Phosphate 

What is Potassium Chloride?

Potassium chloride is an inorganic compound having the chemical formula KCl. This compound is a metal halide that contains a potassium cation bonded to a chloride anion through ionic bonding. Potassium chloride appears as white or colourless vitreous crystals, and it is odourless. Potassium chloride dissolves in water, forming a solution having a salt-like taste.

There are many different uses of potassium chloride; it is useful as a fertilizer known as potash and as a medication to treat low blood potassium levels because potassium is vital to the human body. It is also useful as a salt substitute for food and is important as a chemical feedstock in the chemical industry.

Mainly, potassium chloride is extracted from minerals such as sylvite, carnalite, and potash. We can also extract this compound from saltwater and manufacture it through crystallization processes. In the laboratory, we can produce potassium chloride from the reaction between potassium hydroxide and hydrochloric acid.

What is Potassium Phosphate?

Potassium phosphate is a generic name used for salts of potassium and phosphate ions, which include monopotassium phosphate, dipotassium phosphate, and tripotassium phosphate.

KH₂PO₄ is the chemical formula of monopotassium phosphate. It is also known as MKP, potassium dihydrogenphosphate, KDP, or monobasic potassium phosphate. It is an inorganic compound that is often used as fertilizer along with dipotassium phosphate. The three major uses of KH₂PO₄ are the production of fertilizers, as a food additive in the food industry, and as a buffering agent. Moreover, we can observe that this salt undergoes cocrystallization with dipotassium salt and with phosphoric acid. However, we can see there are single crystals of KH₂PO₄ that are paraelectric at room temperature. They can become ferroelectric at low temperatures. In its commercially available form, KH₂PO₄ is a white powder that is deliquescent.

KH₂PO₄ is the chemical formula of dipotassium phosphate. The other names for this compound are dipotassium hydrogen orthophosphate and potassium phosphate dibasic. It is an inorganic compound that is useful in fertilizer production, as a food additive, and as a buffering agent. This substance appears as a white or colourless solid, which is water-soluble.

K₃PO₄ is the chemical formula of tripotassium phosphate. It is also known as tribasic potassium phosphate. It is an inorganic compound useful as a food additive because it can act as an emulsifier, foaming agent, and whipping agent. It also acts as a catalyst for chemical reactions.

What is the Difference Between Potassium Chloride and Potassium Phosphate?

Potassium chloride is an inorganic compound having the chemical formula KCl. Potassium phosphate is a generic name used for salts of potassium and phosphate ions, which include monopotassium phosphate, dipotassium phosphate, and tripotassium phosphate. The key difference between potassium chloride and potassium phosphate is that potassium chloride has a chloride anion bound to potassium cation, whereas potassium phosphate has one, two, or three phosphate anions bound to potassium cation.

The below infographic presents the differences between potassium chloride and potassium phosphate in tabular form for side by side comparison.

Summary – Potassium Chloride vs Potassium Phosphate

Potassium chloride and potassium phosphate are important inorganic compounds. The key difference between potassium chloride and potassium phosphate is that potassium chloride has a chloride anion bound to potassium cation, whereas potassium phosphate has one, two, or three phosphate anions bound to potassium cation.

Reference:

1. “Potassium Phosphate (Intravenous Route) Side Effects.” Mayo Clinic, Mayo Foundation for Medical Education and Research, 1 Feb. 2022.

Image Courtesy:

1. “Potassium chloride” (Public Domain) via Commons Wikimedia
2. “Monopotassium phosphate” By Edgar181 – Own work (Public Domain) via Commons Wikimedia
3. “Dipotassium phosphate” By Edgar181 – Own work (Public Domain) via Commons Wikimedia