plz plz give all answer
Answers
Hello, here is your answer
2. Thomson's atomic model failed to explain how the positive charge holds on the electrons inside the atom. It also failed to explain an atom's stability. The theory did not mention anything about the nucleus of an atom. It was unable to explain the scattering experiment of Rutherford.
3. Rutherford's model was inadequate to explain the stability of an atom. It did not mention anything about the arrangement of electron in the orbit.
4. In atomic physics, the Bohr model depicts an atom as a small, positively charged nucleus surrounded by electrons. These electrons travel in circular orbits around the nucleus—similar in structure to the solar system, except electrostatic forces rather than gravity provide attraction.
5. (i) An atom consists of a positively charged sphere and the electrons are embedded in it. ... (ii) The electrons revolve around the nucleus in well-defined orbits.
(iii) The size of the nucleus is very small as compared to the size of the atom.
6. (i) The maximum number of electrons present in a shell is given by the formula 2n2, where 'n' is the orbit
number or energy level index, 1,2,3,….Hence the maximum number of electrons in different shells are as
follows:
first orbit or K-shell will be = 2 × 12 = 2,
second orbit or L-shell will be = 2 × 22 = 8,
third orbit or M-shell will be = 2 × 32= 18,
fourth orbit or N-shell will be = 2 × 42= 32,
(ii) The maximum number of electrons that can be accommodated in the outermost orbit is 8.
(iii) Electrons are not accommodated in a given shell, unless the inner shells are filled. That is, the shells are filled in a step-wise manner.
7. Atomic number of silicon is 14. The electronic configuration of the element is-K=2, L=8,m=4. According to the electronic configuration the valency is +4 or -4 because silicon can either gain 4 electrons or lose 4 electrons because it is a noble gas. Hence valency of silicon is 4.