Featured tutorials

Lewis structures and VSEPR shapes

An easy step method can be used to draw lewis structures using the valence electrons.Lewis structures only show the arrangement of electrons in a molecule or compound but does not give any details on shape. In order to find shape of molecules, VSEPR theory is used.Based on presence of lone pairs and bond pairs in a molecule,the shape can be predicted.
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Mendel's Genetics

Early naturalists thought that new species are produced because of a cross between two different species. For example, agiraffe was thought to have been a cross between leopard and camel.The banana was thought to be a cross between acacia and palm.
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Orbital Hybridization

Hybridization is the concept of mixing atomic orbitals to form new hybrid orbitals used for the description of atomic bonding properties. Orbital hybridization is not observed in diatomic molecules such as Hydrogen.
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Kinetic Molecular theory

The main idea of kinetic molecular theory is that the entities(particles)in solids,liquids and gases are in constant and random motion.As entities randomly move, they collide with each other and other objects that are in their way suh as wallsof container. Read More

AP Biology Preparation

AP Biology quizzes organized by chapters can be found here. This list shows all the quizzes available on this site.

AP Chemistry Preparation

AP Biology quizzes organized by chapters can be found here. This list shows all the quizzes available on this site.