What are two key features of the modern model of the atom?

Answer 1

In short, a nucleus that is made up of protons and neutrons which is surrounded by rings of electrons.

More in depth:

A nucleus that contains protons and neutrons which is surrounded by rings of orbiting electrons. The protons have a relative charge* of +1, neutrons a relative charge of 0 and electrons a relative charge of -1. Therefore the nucleus is positively charged and the electrons are negatively charged.

The nucleus of the atom has a much larger mass than the electrons (protons and neutrons have a relative mass number of 1 and electrons a relative mass number of 0.0005).

The electrons arrange themselves around the nucleus in 'energy shells' or rings around the nucleus. Two electrons can fit on the first ring, then eight etc etc.

The electron 'cloud' is so far away from the nucleus that 99.9999999999999% of the atom is just empty space. If you were to stand on the white cliffs of Dover as if you were a nucleus, the distant edges of France in the distance would be the electrons! Everything single thing in the universe is made up of atoms, including ourselves, which makes everything around 99% space as well! Looking at your hand, you wouldn't think that it was predominantly empty, but it is!

There are many different forces at work that keep the atom together. The Electrostatic Force of attraction holds the electrons in the atom because a proton (positively charged) will attract an electron (negatively charged).

However, this force also acts between protons and other protons which means surely that the nucleus would blow itself apart because the protons would all repel each other? The answer is no because there is another force at work; the Strong Nuclear Force which over comes the electrostatic forces of repulsion to keep the atom together!

* When we say relative we mean divided by the mass or charge of a proton. For example, the charge of a proton is 1.60 * 10^-19 so we give it a charge of 1 (1.60 * 10^-19 / 1.60 * 10^-19). Electrons have a mass of 9.11 * 10^-31 so we divide this by the mass of a proton (1.67 * 10^-27) to get 0.0005. This is basically used to make the numbers easier to visualise/ work with.

Hope this helps :)

Answer 2

According to modern model of atom, electrons revolving around the nucleus does not radiate energy continuously. Because the spectra recorded of an atom was found to be line spectra or discontinuous spectra.

Answer 3

To my knowledge, the modern model is the electron cloud atom. It states that Electrons travel in a cloud randomly rather than in orbits. They are more likely to be closer to the atom than further away from it, so the outer edges of the cloud are a lighter color that the center of the cloud. The electrons could be just about anywhere, though.

Answer 4

the modern atomic model is composed of a nucleus in which the protons and neutrons are located, and is also surrounded by an electron cloud in which the energy levels that the electrons are on is located on the outside of the nucleus

Answer 5

Two key features of the modern model of the atom are the existence of a nucleus at the center of the atom, which contains protons and neutrons, and the probability distribution of electrons in electron shells surrounding the nucleus. Additionally, the modern model incorporates the wave-particle duality of electrons, which means they exhibit both particle-like and wave-like properties.

Answer 6

energy of the orbit is related to its size. The lowest energy is found in the smallest orbit.

Answer 7

The modern atom is explained by quantum mechanics.

Answer 8

The quantum mechanical model.