Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Preparation, Properties, and Uses of Phosphine
Introduction
Phosphine is prepared in laboratory scale by using white phosphorus, Sodium Hydroxide followed by warming under inactive environment of the CO2. Phosphine is naturally found in human urine, blood, and saliva. It has several industrial applications as well as some health hazards facts.
Information regarding Phosphine
Phosphine is considered one of the toxic and flammable elements French chemist discovered Phosphine by heating phosphorous $\mathrm{(P_{4})}$ in the presence of aqueous solution of Potassium Carbonate. The experiment resulted in a colourless gas with fishy odour. Phosphine is considered a vital element in biochemical lifecycle. The chemical properties of the element are quite unstable due to the concentration of the compound in the atmosphere.
Structure of Phosphine
The structural geometry of PH3 is trigonal pyramid. The Lewis dot structure of Phosphine contains one lone pair of electron. The other three electrons of Phosphorous atom are shared with three Hydrogen atom to make covalent bond to PH3 molecule.
Figure 1 − Phosphine structure
Additionally, the followings are the considerable facts for Phosphine molecule −
Both the elements, Phosphorous and Nitrogen belong to the group 15 in the periodic table. Molecular structure of PH3 is identical to the NH3 (Ammonia).
Phosphorus shows less electro-negativity than Nitrogen.
The bond angle of H-P-H is 95.3° in Phosphine structure.
The bond length of P-H is 1.42 Å.
Preparation of Phosphine
The preparation of phosphine is done in various steps, the following steps are −
Figure 2 − Preparation of Phosphine gas
Hydrolysis of metal phosphides with Calcium Phosphide − The reaction between the metal phosphides and water or HCl solution results in formation of phosphide.
From phosphorus acid − The procedure of breaking down of H3PO3 can be formulated by the phosphine in pure format.
Preparation from Phosphorus − The process of the production starts with heating process to the white phosphorus can deliver PH3 within the solution of the NaOH where the CO2 environment is available.
$$\mathrm{Ca_{3}P_{2}\:+\:6H_{2}O\:\rightarrow\:2PH_{3}\:+\:3Ca(OH)_{2}}$$
$$\mathrm{4H_{3}PO_{3}\:\rightarrow\:3H_{3}PO_{4}\:+\:PH_{3}}$$
After the formation of the phosphine, purification is very much needed. The availability of the element, $\mathrm{P_{2}H_{4}\:or\:P_{4}}$ makes the phosphine a non-flammable gas. The process of absorbing the HI in the element can transform it into the PH4l . Hence, the procedure of mixing the potassium hydroxide can deliver the phosphine in pure formation.
$$\mathrm{PH_{4}I\:+\:KOH\:\rightarrow\:PH_{3}\:+\:KI\:+\:H_{2}O}$$
Properties of Phosphine
The properties of phosphine can be separated into the two formats as the followings −
Physical properties
The odour that comes from the gas is like rotten fish. The boiling point of the gas is 126°F and the melting point of the gas is equal to 208.8°F . Additionally, it is “lightly soluble in water.
The gas contains a critical temperature of 124.9°F. The gas also contains a gravity of 1.203. It is denoted with the formula of PH3. It has a liquid density of 35.50 at the temperature of 70°F.
Chemical properties
Based on the reaction with other substances the chemical properties can be judged for the PH3. The moment it comes with the interaction of the HBr, HI, and HCl, it can deliver the compounds containing phosphonium ion.
$$\mathrm{PH_{3}\:+\:HBr\:\rightarrow\:PH_{4}Br}$$
$$\mathrm{PH_{3}\:+\:HI\:\rightarrow\:PH_{4}I}$$
$$\mathrm{PH_{3}\:+\:HCl\:\rightarrow\:PH_{4}Cl}$$
This gas is considered a noxious gas. Even a small amount of contraction can make the consequence of side effects like, jaundice, and dizziness. The problem appears in organs such as, in liver and kidney, due to inflammation, nausea, cerebral pain, and fatigue.
Applications of Phosphine
The followings are the critical applications of PH3 in different industries −
In the semiconductor industries, it is applied in small quantities as dopant.
Due to the availability of the properties of spontaneous combustion, it is applied in the Holme’s signal.
The application of the gas can produce as metallic phosphides.
Smoke screen − At the moment, Calcium Phosphide gets absorbed in the water in presence of the Phosphine results in the production of smoke screen s, during several conflicts, it had been deployed in to hide the soldier from the enemy.
Conclusion
Phosphine is considered a colourless gas contains some bad odours. It is used in various industrial applications. Phosphine is considered as toxic one. The gas is not flammable at all in pure form. However, it can be flammable and even explodes when comes in contact with any oxidising substances. It can be prepared in laboratory scale with various applications.
FAQs
1. What are the primary properties of the gas called phosphine?
The primary properties of phosphine are: colourless, toxic, soluble in water, and has a bad fish odour.
2. What is the structure of phosphine?
The geometrical structure of Phosphine is trigonal bipyramidal where, one pair of the electron exists on P atom along with three P–H bonds of length of 1.42Å.
3. How is the phosphine gas prepared in the laboratory of chemistry?
The white phosphorus is heated with concentrated solution of NaOH under inert atmosphere of $\mathrm{CO_{2}}$ results in $\mathrm{PH_{3}}$.
