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Problems of chemical research and changes, it has experienced. As a result of all substance consisting of atoms, it is, your understanding of the atom and its components, especially in electronics.
Why electronic? Due to the electronic configuration determines the chemical bonding and chemical reactions of elements will be how. So, if you understand, you will have a better understanding of chemistry.
However, you must remember, atom and its components is so small, scientists cannot directly with atoms. Therefore, chemists and physicists need to create the model, to help in the atomic description. However, scientific models in the creation of the available information is limited so that, when the new experiment, leading to the discovery of novel mode must change or discard.
Despite the fact that, the scientific model changes, the only way the model to describe how some natural phenomena and knowledge processing function, further scientific discovery is often critical. So, is it right? The truth of human model, model is the best estimate is how to work. For this reason, model of the importance, is it right? Their reasons, but its maneuverability.
Remember, the model is created by humans, can be biased and inaccurate, defect. Always in the scientific method to study model, and was willing to abandon, do not measure.
. although the model is not perfect, there are five problems understanding, leading to the atomic model. The more you know about these models better, you will be in Chemistry Molecular Models . The five models are: these five types of models:
A solid ball model
Plum pudding model
Nuclear model
Bohr model
The wave mechanical model
A solid ball model
A solid sphere model, proposed in 1803 by John Dalton. John Dalton is a British chemistry and mathematics tutor, he daily thoughts and into the problem is how to arrange mode. He points out, whether it is called the same element atom and atom are the same indivisible particles. In addition, he also includes multiple proportion of law and law in his model. Although he is not a perfect model, which is mainly for over 90 years the main models.
Raisin pudding
In 1897 the British physicist Tom, suggest, cathode ray is negatively charged particles smaller than atoms. In fact, he suggests, these particles are atoms, subatomic part. Therefore, Dalton's one indivisible particle theory is no longer feasible. Subatomic particles allows for a new theory, is necessary.
Therefore, Tomson proposed that atoms of positive charge and negative electron like plum pudding, and identified by the plum pudding model. . Tomson 's model, although attractive, however there are many
Defect.
Nuclear model
1906, Rutherford and his assistant, experiment, the discovery of the atomic nucleus and atomic is the main space leading gold.
Gold foil experiment show that, the mass of an atom is the same, Thompson model prediction, but large-scale smaller, seems to be in the atomic center located in. Tomson plum pudding model is no longer viable. Thus, in the 1911, Rutherford proposed atomic nuclear model.
Bohr model
In 1913, Danish physicist Bohr Neils, it is suggested that the application of quantum theory, Rutherford model. Bohr's new model, electronic at fixed energy levels, he called the orbital. These orbital energy is quantized electronic must be in a specific wavelength absorption or release energy ( photons ) energy levels between mobile.
The wave mechanical model
In 1921, De Broglie said, without any experience to any places according to, if waves have properties of matter, then the problem should have wave properties. . later, Baer laboratory will prove the De Broglie hypothesis is, is indeed the right. De Broglie's hypothesis is a revelation, or even left a deep impression, Einstein and change the atomic forever.
Louis - De Broglie's hypothesis and Bohr's model combination, Schrodinger puts forward a three-dimensional wave circled in the allowed waveform, to repeat as a stable permanent representative Bohr model of the energy level and wave itself the wavelength of the integer core electron
