Online Class 12 Chemistry Notes- Unit 1- Band Theory of Solids

Band Theory of Solids: A quantum mechanical model of electrons in solids that predicts certain restricted ranges or the bands, for the energies of these electrons is called as Band Theory of Solids. It is also called as energy band theory of solids. The behavior of an electron in a solid (and hence its energy) is related to the behavior of all other particles around it. This is in direct contrast to the behavior of an electron in free space where it may have any specified energy. The ranges of allowed energies of electrons in a solid are called allowed bands. Certain ranges of energies between two such allowed bands are called forbidden bands—i.e., electrons within the solid may not possess these energies. The band theory accounts for many of the electrical and thermal properties of solids and forms the basis of the technology of solid-state electronics.

A useful way to visualize the difference between conductors, insulators and semiconductors is to plot the available energies for electrons in the materials. Instead of having discrete energies as in the case of free atoms, the available energy states form bands.

Important energy bands in solids

There is a number of energy bands in solids but three of them are very important. These three energy bands are important to understand the behavior of solids. These energy bands are

Valence band
Conduction band
Forbidden band or forbidden gap

Read complete chapter click Class 12 Chemistry Notes- Unit 1- Band Theory of Solids

For more chemistry notes, CBSE Class 12 Chemistry articles, video lectures, CBSE exam alerts, Syllabus, sample papers and NCERT solutions for Class 12th, log in with Takshila Learning.

Comments

Last Minute Tips to Crack SSC CGL 2019-20 (Tier-I) Exam

Last-Minute Tips to Crack SSC CGL 2019-20 (Tier-I) Exam 1. Don’t read any new topic at the last moment · Try to avoid studying any new topic at the last moment. Just revise what you have already studied. 2. Don’t forget your Admit Card, Photograph and ID Proof · Take a print out of your admit card and original photo identity proof, 1 photo and photocopy of the ID proof. Reach the examination center before time to avoid any last-minute trouble. 3. Maintain your Speed & Accuracy and Maximize your Score · Speed and Accuracy are two important factors to crack any competitive exam. Speed will help in maximizing the attempts while accuracy will ensure that you don’t end up losing marks as the negative marking of 0.5 marks for wrong answers is there. 4. Attempt according to the strategy you followed in the mock tests · Make sure you attempt the easier section first. The exam should be attempted with the same strategy you fol

Magnetic and non-magnetic material Class 6 Science

Magnetic and non-magnetic material Class 6 Science A magnet is a substance that is drawn to certain magnetic materials like iron, cobalt, and nickel. Magnets have the ability to draw iron to them. Natural magnets are rocks that naturally draw iron. Non-magnetic materials include things like wood, rubber, coins, feathers, leather, etc. that are not drawn to iron. Magnet characteristics It pulls magnetic materials, such as iron. The magnet's two ends are referred to as its poles. The magnet's diametrically opposed poles are drawn together. Heating, hammering, or dropping causes it to lose its characteristics. On the basis of properties types of Magnets Temporary magnets are those magnets that are magnetic for only a little duration. Typically, iron, cobalt, or nickel are used to make them. When they are close to the powerful magnet, they act like a magnet. When they are yanked away from the powerful magnet, they stop being magnetic. Permanent magnets are magnets that have magne

Why is Hindi Day celebrated on 14 September?

Why is Hindi Day celebrated on 14 September? After independence, the Government of India set a goal to give an ideal form to the mother tongue of the country and set a target for grammar and orthography using the Devanagari script to bring standardization in writing. Subsequently, on September 14, 1949, the Constituent Assembly decided by a vote that Hindi would be the official language of India. To propagate the importance of this decision and to spread Hindi in every region, India is celebrating Hindi Day every year from 1953 to 14 September, at the request of Rashtrabhasha Prachar Samiti, Wardha. Apart from this, 14 September is also the birthday of Rajendra Singh, who worked tirelessly to make Hindi the official language of India. Hindi Day is observed every year on 14 September to mark the importance of the Hindi language in the country. The Hindi language is one of the oldest languages, which derives most of its academic vocabulary from the Sanskrit language written in the Deva

Takshila Learning - Online Tutorials

Search This Blog