Question

1. explain the similarities and differences between the plum pudding model and the bohr model of the atom. draw a sketch to illustrate your answer. (6.6) ku c

Explanation:

Similarities:

• Both models recognize the existence of electrons within the atom. In the plum pudding model, electrons are embedded in a positively - charged “pudding”, and in the Bohr model, electrons orbit the nucleus.
• Both models also acknowledge that the atom has a positively - charged component. In the plum pudding model, the “pudding” is positively charged, and in the Bohr model, the nucleus is positively charged.

Differences:

• Structure of positive charge: In the plum pudding model, the positive charge is spread out uniformly throughout the atom (like a pudding), while in the Bohr model, the positive charge is concentrated in a small, dense nucleus at the center of the atom.
• Electron arrangement: In the plum pudding model, electrons are embedded randomly in the positive “pudding”. In the Bohr model, electrons move in specific, circular orbits (energy levels) around the nucleus. The orbits have fixed energies, and electrons can jump between these orbits by absorbing or emitting energy.
• Size and density concept: The plum pudding model does not have a distinct nucleus, so the atom is considered to have a more uniform density. The Bohr model has a very small, dense nucleus, and most of the atom's volume is empty space occupied by the electron orbits.

Sketch Description (for illustration):

• Plum Pudding Model Sketch: Draw a circle to represent the atom. Inside the circle, draw a shaded (or colored) region to represent the positively - charged “pudding”. Then, draw small dots (representing electrons) scattered randomly within this shaded region.
• Bohr Model Sketch: Draw a small, dense circle at the center to represent the nucleus (label it with a “+” sign to indicate positive charge). Then, draw one or more concentric circles around the nucleus to represent the electron orbits (energy levels). Place small dots (electrons) on these orbits. You can label the orbits with different energy level designations (e.g., n = 1, n = 2, etc.) to show the different energy levels.

Answer:

Similarities:

• Both include electrons and a positive - charge component in the atom.
• Both recognize the presence of electrons within the atom's structure.

Differences:

• Plum Pudding: Positive charge is spread, electrons are embedded randomly. Bohr: Positive charge is in a dense nucleus, electrons orbit in fixed energy levels.
• Plum Pudding has no distinct nucleus, Bohr has a small, dense nucleus.

Sketch (description):

• Plum Pudding: Circle with shaded positive region and random electrons. Bohr: Small nucleus at center, concentric orbits with electrons on them.