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What is Energy ? Energy— Carbohydrate, protein and fat are main energy producing food substances. Oxygenationof these provides energy. This energy is used for various functions and processes of the body. Energy is required for voluntary activities like running, walking, sleeping, cooking etc. and for involuntary activities like breathing, blood circulation, heart beating, etc. Calorie…
What is Isobars ? What is Isobars : Isobars are the atoms of different elements whose mass number is the same but atomic number differs. For example, the mass number of calcium and argon, both, is 40 but their atomic number are 18 and 20 respectively. Similarly, mass number of Carbon-14 and Nitrogen-14, is 14…
What is Isotopes And Uses of Isotopes What are Isotopes : According to Dalton’s Atomic Theory all the atoms of an element are similar. But later on, scientists found that this was not true. They found that the mass number of the atoms of the same element may differ. Hydrogen atom is an example which…
What is the Position of electron inside Atom ? Position of electron :- In an atom the electrons revolve around the nucleus in definite orbitals. These orbitals were represented by Bohr as K, L, M, N, O or 1, 2, 3, 4, 5. The number of electrons in each orbital is 2n where n is…
What is Avogadro Number ? What is Avogadro Number :- Hydrogen and oxygen reacts to form water : 2H2 + O2 = 2H2 O In this reaction 2 molecules of hydrogen react with one molecule of oxygen to form two molecules of water. The amount of substances taking part in a reaction can be determined…
Atomic weight | Definition, Units, & Table What is Atomic weight :- With the studies regarding atomic structure, the knowledge of e/m (i.e. ratio of charge to mass) of the electron had developed. Over period of time, even the atomic weight was determined. In the beginning the weight of atoms was calculated in relation to…
What is Atomic Mass ? Atomic Mass Definition Atomic Mass Definition :- According to Dalton’s atomic theory, each element has its characteristic atomic mass. Dalton’s theory can easily explain the law of constant proportion, hence, inspired by it the scientists advanced towards measuring the atomic mass and relative atomic mass, using the combination rules. Practically…
Bohr’s Model of The Hydrogen Atom Bohr’s Model of Hydrogen Atom : Rutherford’s atomic model was not in accordance with the laws of Physics. In 1912 Neil Bohr presented a new atomic model based on concepts. The main postulates of the Bohr’s hydrogen atom model, based on the quantum theory, are as under : In…
Discovery of Neutrons Discovery of Neutrons : Atomic studies revealed that the mass of atom is more than total mass of electron and protons present therein. In 1920, Ernest Rutherford suggested the presence of neutral particles in the atom but in was difficult to identify them because they were without any charge. In 1932 the…
Rutherford’s Experiment and the Nuclear Atomic Model Rutherford’s Experiment and the Nuclear Atomic Model : In 1911, Ernest Rutherford bombarded a thin screen i.e. foil of gold (100 nanometer or 10-7 meter thick) encoated with zinc sulphide, with alpha particles (Helium nuclei). The following observations were made by this experiment : Most of the particles…