Electron Structure of Atoms: Bohr's Model

Flashcards covering the electron structure of atoms, Bohr's Model, atomic definitions, subatomic particles, and related concepts from the lecture.

What phenomenon occurs when light strikes an atom and only specific colors are absorbed?

The quantization of the atomic absorption spectrum.

What is the primary goal related to atomic properties and the periodic table in this course?

To understand the chemical similarities of atoms by describing their electron structure.

According to the lecture, what is the definition of a solid?

A sample of matter that can retain its volume and shape, at variance with a liquid or a gas.

What are the key characteristics that differentiate solids, liquids, and gases?

Solids are incompressible and rigid; Liquids are incompressible and not rigid; Gases are not incompressible and not rigid.

What is the 1st definition of an atom, and from what ancient Greek word does it originate?

Atoms are the elementary chemical constituents of matter that cannot be broken during a chemical reaction. The word 'atom' comes from 'átomos', meaning 'impossible to cut'.

Can an atom be broken?

By definition, atoms cannot be broken in a chemical reaction, but they can be broken into smaller particles through processes like nuclear reactions or natural radioactivity.

What are the subatomic particles that make up an atom, according to the 2nd definition?

Atoms consist of a central nucleus made of protons and neutrons (nucleons) surrounded by electrons.

How is an atom commonly denoted, and what do the symbols A and Z represent?

An atom is denoted as AXZ, where X is the symbol of the atom, Z is the number of protons (atomic number), and A is the total number of nucleons (mass number).

What is the mass defect in the context of atoms?

The mass defect is the unexpected discrepancy where the mass of an atom is not the sum of the masses of its isolated subatomic constituents.

What is the condition for an electron to escape a proton?

An electron must have a kinetic energy greater than its absolute electrostatic energy to escape the proton.

What is angular momentum, and when is it a constant of motion?

Angular momentum (L) of a particle is the product of its mass (m), distance to a point (r), and angular coordinate of particle velocity (vθ), L = mrvθ. It is a constant of motion whenever the force acting on the particle is radial with no angular component.

According to Bohr's model for the hydrogen atom, what are the possible electron energies?

The possible electron energies (En) are given by En = -E0/n^2, where n = 1, 2, … and E0 = 13.60 eV.

In Bohr's model for the hydrogen atom, what are the corresponding radii of circular orbits?

The corresponding orbit radii (rn) are given by rn = a0*n^2, where a0 is the Bohr radius (0.529 Å).

What happens when hydrogen absorbs a light ray whose energy matches one of the differences (En+ - En-)?

Its electron undergoes the transition from n- to n+.

What happens when an excited electron in hydrogen transitions to a lower energy level (n+ to n-)?

It emits a light ray whose energy equals the difference (En+ - En-).