The key difference between calcium chloride and potassium chloride is that in the flame taste, calcium chloride gives a brick red flame due to the presence of calcium cation whereas potassium chloride gives a violet flame due to the presence of potassium cation.
Both calcium chloride and potassium chloride are inorganic substances we can categorize as metal halides because these compounds contain metal cations and nonmetal anions bonded with each other via ionic bonding. These are crystal lattice structures.
CONTENTS
1. Overview and Key Difference
2. What is Calcium Chloride
3. What is Potassium Chloride
4. Side by Side Comparison – Calcium Chloride vs Potassium Chloride in Tabular Form
5. Summary
What is Calcium Chloride?
Calcium chloride is an inorganic compound having the chemical formula CaCl2. It is a chloride salt of calcium. We can observe this substance as a white coloured crystalline solid at room temperature. This material is highly water-soluble.
Figure 01: Calcium Chloride
Calcium chloride is commonly known as a hydrated substance; the number of water molecules that are associated with one calcium chloride molecule can be 0, 1, 2, 4 or 6. Usually, these hydrates are important as de-icing agents and as dust control agents. Moreover, anhydrous CaCl2 substance is useful as a desiccant due to its hygroscopic nature.
Calcium chloride can be prepared from limestone as a byproduct of the Solvay process. The Solvay process is the method of producing sodium carbonate, where calcium chloride forms along with sodium carbonate. The reaction involves sodium chloride and calcium carbonate (from limestone). However, we can also make this substance from the purification of brine solution.
Typically, calcium chloride is considered a non-toxic compound. However, due to its hygroscopic property, the anhydrous form of this compound can be hazardous. It can act as an irritant to the skin by desiccating the moist skin.
What is Potassium Chloride?
Potassium chloride is an inorganic compound having the chemical formula KCl. It is a metal halide that contains a potassium cation bonded to a chloride anion through ionic bonding. This substance appears as white or colourless vitreous crystals, and it is odourless. Potassium chloride dissolves in water, forming a solution having a salt-like taste.
Figure 02: Potassium Chloride
There are many different uses of potassium chloride; it is useful as a fertilizer named as potash, as a medication to treat low blood potassium levels because potassium is vital to the human body. It is useful as a salt substitute for food and is also 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 the Difference Between Calcium Chloride and Potassium Chloride?
Calcium chloride and potassium chloride are inorganic compounds. The key difference between calcium chloride and potassium chloride is that calcium chloride gives a brick red flame for the flame test due to the presence of calcium cation whereas potassium chloride gives a violet flame for the flame test due to the presence of potassium cation. This is the way we can distinguish these two compounds easily.
The below infographic shows more differences between calcium chloride and potassium chloride.
Summary – Calcium Chloride vs Potassium Chloride
Calcium chloride and potassium chloride can be named as metal halides because these compounds contain metallic cations and nonmetallic anions. The key difference between calcium chloride and potassium chloride is that calcium chloride gives a brick red flame for the flame test due to the presence of calcium cation whereas potassium chloride gives a violet flame for the flame test due to the presence of potassium cation.
Reference:
1. “Potassium Chloride.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine, Available here.
Image Courtesy:
1. “Calcium chloride CaCl2” – Firetwister assumed – No machine-readable source provided. Own work assumed (based on copyright claims). (CC BY-SA 3.0) via Commons Wikimedia
2. “Potassium chloride” (Public Domain) via Commons Wikimedia