1. Thomson's model: An atom consists of a positively charged sphere with electrons embedded in it. Rutherford's model: • An atom consists of a positively charged particles concentrated at the center known as the nucleus. • The size of the nucleus is very small as compared to the size of the atom. • TheRead more

    Thomson’s model: An atom consists of a positively charged sphere with electrons embedded in it.

    Rutherford’s model:
    • An atom consists of a positively charged particles concentrated at the center known as the nucleus.
    • The size of the nucleus is very small as compared to the size of the atom.
    • The electron revolve around the nucleus in well – defined orbits.

    Bohr’s model:
    • There are only certain orbits know as discrete orbits inside the atom in which electrons revolve around the nucleus. Electrons do not radiate energy while revolving.

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  2. Bohr’s model of the atom Niels Bohr proposed the following postulates regarding the model of the atom. (i) Only certain orbits known as discrete orbits of electrons are allowed inside the atom. (ii) While revolving in these discrete orbits, the electrons do not radiate energy. The first orbit (i.e.,Read more

    Bohr’s model of the atom Niels Bohr proposed the following postulates regarding the model of the atom.
    (i) Only certain orbits known as discrete orbits of electrons are allowed inside the atom.
    (ii) While revolving in these discrete orbits, the electrons do not radiate energy.
    The first orbit (i.e., for n = 1) is represented by letter K. Similarly, for n = 2, it is L − shell, for n = 3, it is M − shell and for n = 4, it is N − shell. These orbits or shells are also called energy levels.

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  3. According to Rutherford’s model of an atom, electrons revolve around the nucleus in fixed orbits. But, an electron revolving in circular orbits will not be stable because during revolution, it will experience acceleration. Due to acceleration, the electrons will lose energy in the form of radiationRead more

    According to Rutherford’s model of an atom, electrons revolve around the nucleus in fixed orbits. But, an electron revolving in circular orbits will not be stable because during revolution, it will experience acceleration. Due to acceleration, the electrons will lose energy in the form of radiation and fall into the nucleus. In such a case, the atom would be highly unstable and collapse.

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  4. According to J.J. Thomson’s model of an atom, an atom consists of a positively charged sphere with electrons embedded in it. However, it was later found that the positively charged particles reside at the center of the atom called the nucleus, and the electrons revolve around the nucleus. For more aRead more

    According to J.J. Thomson’s model of an atom, an atom consists of a positively charged sphere with electrons embedded in it. However, it was later found that the positively charged particles reside at the center of the atom called the nucleus, and the electrons revolve around the nucleus.

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  5. Electron: (i) Electron are present outside the nucleus of an atom. (ii) Electron are negatively charged. (iii) The mass of an electron is considered to negligible. Proton: (i) Proton are present in the nucleus of an atom. (ii) Proton are positively charged. (iii) The mass of a proton is approximatelRead more

    Electron:
    (i) Electron are present outside the nucleus of an atom.
    (ii) Electron are negatively charged.
    (iii) The mass of an electron is considered to negligible.

    Proton:
    (i) Proton are present in the nucleus of an atom.
    (ii) Proton are positively charged.
    (iii) The mass of a proton is approximately 2000 times as the mass of an electron.

    Neutron:
    (i) Neutron are present in the nucleus of an atom.
    (ii) Neutron are neutral.
    (iii) The mass of neutron is nearly equal to the mass of a proton.

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