The key difference between liquid oxygen and gas oxygen is that liquid oxygen has comparatively a small distance between two oxygen molecules, whereas gas oxygen has a considerably high distance between the oxygen molecules.
Oxygen is a very important chemical element. It can occur in two major ways as liquid oxygen and gas oxygen. Among them, gas oxygen is the most common and essential form of oxygen, whereas liquid oxygen has industrial needs.
CONTENTS
1. Overview and Key Difference
2. What is Liquid Oxygen
3. What is Gas Oxygen
4. Liquid Oxygen vs Gas Oxygen in Tabular Form
5. Summary – Liquid Oxygen vs Gas Oxygen
What is Liquid Oxygen?
Liquid oxygen is the liquid form of molecular oxygen. It has major applications in aerospace, gas industries, and submarines. We can abbreviate this form of oxygen as Lox, LOX or as Lox. In 1926, Robert H. Goddard used this liquid oxygen as the oxidizer in his first liquid-fueled rocket invention.
Figure 01: Appearance of Liquid Oxygen
Usually, liquid oxygen gas has a light blue colour. This substance is highly paramagnetic; therefore, we can make it suspended between the poles of powerful magnets. Its density is about 1141 g/L, which is slightly denser than liquid water. Moreover, this substance is cryogenic, having a very low freezing point and a boiling point. Due to this cryogenic nature of liquid oxygen, it can cause the material it touches to be extremely brittle.
Furthermore, liquid oxygen is a powerful oxidizing agent. Therefore, organic materials can burn rapidly and energetically in the presence of liquid oxygen. Some materials (e.g. coal) can give an unpredictable flame if they are soaked in liquid oxygen.
When considering the structure of liquid oxygen, it was believed to have tetraoxygen molecules, O4, which was predicted as such in order to defy Curie’s law. However, according to some modern computer simulations, there cannot be any stable O4 molecules in liquid oxygen. Therefore, now it’s believed to have O2 molecules, which are associated in pairs under antiparallel spins that can form transient O4 units.
What is Gas Oxygen?
Gas oxygen is the gaseous state of molecular oxygen. At standard conditions, gas oxygen is a colourless, odourless, and tasteless gas having the molecular formula O2. When comparing the dissolution of oxygen and nitrogen in the water, oxygen tends to dissolve more rapidly. It readily dissolves in freshwater compared to seawater. However, this water solubility of gas oxygen depends on the temperature because, at high temperatures, solubility becomes low.
Figure 02: Use of Oxygen Gas for Photosynthesis
Apart from that, gas oxygen is the most abundant chemical element by mass on Earth’s biosphere, air, sea, and land. In the universe, it is the 3rd most abundant chemical element (comes after hydrogen and helium). The high content of oxygen in our planet makes it unusual among other planets of the Solar System and is the most probable reason for life on Earth. The oxygen on Earth causes the oxygen cycle, which describes the movement of oxygen within and between the atmosphere, biosphere and lithosphere.
What is the Difference Between Liquid Oxygen and Gas Oxygen?
As their names imply, liquid oxygen is the liquid form of molecular oxygen, while gas oxygen is the gaseous state of molecular oxygen. The key difference between liquid oxygen and gas oxygen is that liquid oxygen has comparatively a small distance between two oxygen molecules, whereas gas oxygen has a considerably high distance between the oxygen molecules. Moreover, concerning the appearance, the liquid oxygen is pale blue in colour, paramagnetic, and cryogenic substance that can make other materials brittle, whereas gas oxygen is colourless, tasteless, odourless gas at standard temperature and pressure.
Below is a summary of the difference between liquid oxygen and gas oxygen in tabular form.
Summary – Liquid Oxygen vs Gas Oxygen
Liquid oxygen is the liquid form of molecular oxygen. Gas oxygen is the gaseous state of molecular oxygen. The key difference between liquid oxygen and gas oxygen is that liquid oxygen has comparatively a small distance between two oxygen molecules, whereas gas oxygen has a considerably high distance between the oxygen molecules.
Reference:
1. “Oxygen.” Wikipedia, Wikimedia Foundation.
Image Courtesy:
1. “Liquid oxygen in a beaker 4” By U.S. Air Force: Staff Sgt. Jim Araos – (Public Domain) via Commons Wikimedia
2. “Simple photosynthesis overview” By Daniel Mayer (mav) – original imageVector version by Yerpo – Own work (CC BY-SA 4.0) via Commons Wikimedia