The atomic number of an element tells you the number of protons within said element.
Explanation: Entropy decreases when the number of moles of gas decreases during a reaction. In the case of the correct answer, the number of moles of gas decreases from two to one. When a substance goes from a solid to a gas (sublimation) or from a liquid to a gas (evaporation), entropy increases.
Answer:
Is used to predict the spectra of hydrogen and hydrogen like species
Explanation:
The Bohr's model of the atom was propounded by Neis Bohr. In his theory, an atom is composed of quantized energy levels in which electrons may be found.
The transition of an electron between energy levels leads to the absorption or emission of energy in the form of a photon of visible light. The energy absorbed or emitted depends on the energy difference between the two energy levels.
The model is successful at predicting the electronic spectra of one electron species but totally fails when the specie has more than one electron. Also, the model fails to show the true shape of the electron orbitals within an atom.
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