Question

Please help!!

(this is Rutherford's Black box experiment and atoms)

- please answer all the questions in full sentences :D

- do not answer "i'm not sure" on here.


1) Suppose the marble usually rolled right to the end of the box without bouncing off anything, what would this tell you about the size of the targets?



2) What conclusions did Rutherford draw from his data and how did the data change the model of the atom?



3) Niels Bohr was a student of Rutherford, Bohr's work went on to modify the atomic model even more. What changes did Bohr make to advance our understanding of the atom?

Answer 1

Suppose the marble usually rolled to the end of the box without bouncing off anything, it would mean the targets inside are small, much like how Rutherford's experiment indicated atoms are mostly empty space with a small, dense nucleus. Rutherford's discovery led to the nuclear model of the atom with a central nucleus and surrounding electrons, later refined by Niels Bohr's model of quantized electron orbits. Protons' positive charge is offset by neutrons and the strong nuclear force in the nucleus.

Step-by-step explanation:

Rutherford's Experiment and the Atomic Model

If the marble in an experiment similar to Rutherford's Black box usually rolled right to the end of the box without bouncing off anything, this would indicate that the targets inside the box are very small or take up a tiny fraction of the space within the box. This is analogous to Rutherford's gold foil experiment, where most of the alpha particles passed through the gold foil without deflection, suggesting that atoms are mostly empty space with a small, dense nucleus.

Rutherford changed our thinking about atomic structure by proposing the nuclear model of the atom, where a positively charged nucleus is surrounded by electrons. Prior to his work, the prevailing model was the plum pudding model, where positive and negative charges were thought to be distributed evenly throughout the atom. Rutherford's gold foil experiment showed that this was not the case, as some alpha particles were deflected at large angles, indicating a concentrated positive charge in the center of the atom.

Niels Bohr, a student of Rutherford, advanced our understanding of the atom by proposing that electrons orbit the nucleus in fixed energy levels or shells. This explained why atoms emit light at specific wavelengths, as electrons move between these quantized orbits.

Protons being positively charged was problematic in earlier models because they should repel each other and cause the nucleus to disintegrate. However, it is explained by the presence of neutrons and the strong nuclear force which holds the nucleus together. Additionally, Rutherford's model required electrons to be in motion to avoid falling into the nucleus due to electrostatic attraction.

Answer 2

1) Suppose the marble usually rolled right to the end of the box without bouncing off anything, what would this tell you about the size of the targets?

That the target is very small, they do not take up much space in the box. The target represents the gold nuclei in the Rutherford experiment, and thus is relatively small.

2.) What conclusions did Rutherford draw from his data and how did the data change the model of the atom?

A large majority of the alpha particles went through the gold foil, but some got deflected back. At the time, it was presumed that an atom was a sphere with the same charge all around. If some but not all the particles were being reflected back, this meant that the positive charge in the atom must be very concentrated- ie. in the center known as a nucleus. This changed the atomic model from the plum pudding model (negative electrons among large positive sphere) to the nuclear model (Mass of atom is in the nucleus with electrons orbiting around). (As in image below)

3) Niels Bohr was a student of Rutherford, Bohr's work went on to modify the atomic model even more. What changes did Bohr make to advance our understanding of the atom?

Instead of random orbits that Rutherford predicted, Bohr proposed specific atomic orbitals. He explained that there are orbital levels around the nucleus and that this is where electrons are. He said that electrons can move up energy levels by adding energy, and move down by releasing energy. These orbitals are what is shown in the Bohr Model.

Hope this helps!