Chemistry, asked by kanchu2785, 8 months ago

Compare all proposed models of an atom given in this lesson

Answers

Answered by hari748

Daltons atomic theory

Matter consists of indivisible particles called atoms
Atoms are neither created nor destroyed in a chemical reactoon.Reorganisation of atoms occur in chemical reactions
All the atoms of same element have identical mass and identical chemical properties.atoms of different elements have different masses and different chemical properties.
Compounds are formed when atoms of different elements combine in simple whole no. ratios

Thomson model of the atom .

an atom is considered to be a sphere of uniform positive charge and electrons are embedded in it.
The total mass of the atom is considered to be a uniformly distributed through out the atom .
The negative and the positive charges are supposed to balance out and the atom as a whole is electrically neutral.

Most of the space inside the atom is empty because most of the alpha particles passed through the gold foil.
A very small fraction of alpha particles that were deflected right back indicated that they had met a very charged positive charge and mass repelled the charge on the alpha particle.
all the positively charged particles in atom formed a small dense centre called the nucleus of the atom . The electrons were not a part of nucleus.
the negatively charged electrons revolve around the nucleus in well defined orbits.
The size of the nucleus is very small as compared to the size of an atom.

The electrons revolves around the nucleus in certain discrete circular orbiatals of the atom.These orbits or shells are called energy levels.
while revolving in these discrete orbits the electrons do not radiate energy and this the reason why electrons do not fall into the nucleus.
The electron orbits or shells are represented by the letters K,L,M,N....or the no.s n=1,2,3,4...