1state relative mass and charge of an electron
2 an atom of an element X may be written as 4X^9 (a)What does the figure 9 indicate? (b)what is the number of protons in an atom X? (c)what is the number of electrons in an atoms X? (d)what does the number 4 indicate?
3 describe the rutherfords nuclear madel of an atom
I did the last one (above) for you. Not this one. I'll be glad to explain what you don't understand but not another 6 freebies.
1. The relative mass of an electron is approximately 1/1836th the mass of a proton or a neutron. Its charge is -1 elementary charge (-1e).
To find this information, you can refer to any scientific resource, such as a textbook, an online article, or a reference book. These sources will provide the precise value of the relative mass and charge of an electron.
2. (a) The figure "9" in 4X^9 represents the mass number of the atom X. The mass number is the sum of the protons and neutrons present in the nucleus of an atom.
(b) The number of protons in an atom X can be determined by identifying the atomic number of the element. In this case, it is not provided directly, but by knowing that the element X is written as 4X^9, we can infer that the atomic number is 4. Therefore, there are 4 protons in an atom X.
(c) The number of electrons in a neutral atom is equal to the number of protons. Since we already identified that there are 4 protons in atom X, there are also 4 electrons in atom X.
(d) The number "4" before the symbol X indicates the atomic mass of the atom X. It tells us the total number of nucleons (protons and neutrons) present in the nucleus of the atom.
3. The Rutherford nuclear model of an atom, also known as the planetary model or the nuclear model of the atom, was proposed by physicist Ernest Rutherford in the early 20th century. This model suggests that an atom consists of a small, dense, positively charged nucleus at its center, while the negatively charged electrons orbit around the nucleus in circular paths.
According to this model:
- The nucleus contains most of the atom's mass and is extremely small compared to the overall size of the atom.
- The electrons revolve around the nucleus in distinct energy levels or shells.
- Electrons move in fixed orbits and do not spiral into the nucleus due to the balance between their centripetal force and the electrostatic attraction between the electrons and the nucleus.
- The positive charge of the nucleus is balanced by the negative charge of the electrons, making the atom electrically neutral.
This model was a significant step in understanding the structure of atoms, although it has since been modified with the development of quantum mechanics.