Niels Bohr's contribution to chemistry
By: Helena Whyte
Niels Bohr proposed a model for the hydrogen atom where the negatively charged electron is attracted to the positively charged proton. Bohr said that electrons move in fixed orbits around the nucleus of the atom. This model is called the planetary model of the atom...
By: Sherry Horton Blake
The title, “Understanding the Law of Conservation of Mass,” sounds very scientific and complex. However, in reality, it’s really very simple. The law of conservation of mass just says this, “Mass is neither created nor destroyed in any ordinary chemical reaction...
What are Ven der Waals forces?
By: Elaine Sihera
All molecules experience intermolecular attractions because molecules attract each other at moderate distances and repel each other at close range. The attractive forces are collectively called "Van der Waals forces" and include all forces that act between electrically neutral molecules in both liquid and solid...
By: Ramona Taylor
In ancient times, philosophers and scientists did not have a clear view of the atom. From Democritus's time to the 1800s, scientists were unable to explain basic chemical reactions or understand the elements. Then, came John Dalton, a schoolteacher and chemist, who sought to bring...
Famous Asian chemists and their contributions to chemistry
By: Brian Dodson
The historic foundations of chemistry were mainly established by Asian chemists of the first millennium AD. The centers for this intellectual and scientific development were primarily in the Middle East and in China. These disparate schools drove the transition of chemistry from superstition to science...
The basis for Dalton's atomic theory
By: Helena Whyte
John Dalton's Atomic Theory is based on the facts known in 1808. The Atomic Theory states that all elements are made up of atoms. Atoms of an element are all alike. Atoms are not created or destroyed in chemical reactions. Chemical reactions take place between...
By: Luke Buffington
For thousands of years some of the greatest minds in history have attempted to classify all of the known substances in existence. Although many great thinkers had attempted this feat no one was able to come up with a satisfactory explanation and organization for the...
Famous Asian chemists and their contributions to chemistry
By: Ramona Taylor
Chemistry is an old science! Born out of the alchemist's lab, it has come to represent the study of interactions between matter and energy. The sister science to physics, chemistry focuses more on the properties of substances and their atomic and sometimes subatomic interactions. It...
How fireworks get their colors
By: Brian Dodson
What could be more exciting that the finale of a fireworks display? The endless bursts of color, the detonations, the feeling that the fireworks are going to envelop you – well, it just doesn’t get much better than the combination of terror and delight...
How to determine the concentration of substances in a diluted solution
By: Brian Dodson
A solution such as salt water is a uniform mixture of one or more solutes (e.g., salt) in a solvent (water). For this article we will assume the solvent is a liquid, but there are solid solutions as well. The solute (the substance dissolved...

 

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