Atomic Spectra Flashcards
What is atomic spectra?
The spectrum of frequencies off electromagnetic radiation emitted or absorbed during transitions of electrons btw energy levels within an atom.
What is a line emission spectrum?
A line emission spectrum is a spectrum that consists of discrete lines, each corresponding to a specific wavelength of light emitted by atoms or molecules when they transition from a higher energy state to a lower energy state.
True or False: The line emission spectrum can be used to identify elements in a sample.
True
Fill in the blank: The phenomenon of line emission occurs when electrons in an atom ______.
drop to lower energy levels
Which of the following elements has a line emission spectrum that includes the Balmer series? A) Helium B) Hydrogen C) Neon D) Argon
B) Hydrogen
What is the significance of the wavelengths in a line emission spectrum?
The wavelengths in a line emission spectrum correspond to the energy differences between electron energy levels in an atom, allowing for the identification of the element.
What is line absorption?
Line absorption refers to the process where specific wavelengths of light are absorbed by atoms or molecules, resulting in a decrease in intensity at those wavelengths.
True or False: Emission lines are produced when an electron transitions from a higher energy level to a lower energy level.
True
Fill in the blank: In line absorption spectra, dark lines represent the __________ of light at specific wavelengths.
absorption
Which phenomenon occurs when light passes through a cool gas and specific wavelengths are absorbed?
Line absorption
What is the relationship between line emission and temperature?
Higher temperatures can lead to more energetic transitions, resulting in more intense line emission.
The longest wavelength corresponds to which n= and how much is it predicted?
n=3 and 656.2nm.
Radius of circular orbit formula?
r= n^2 x 0.53 x 10^-10 m.
Energy of electron formula?
En = -13.6/n² eV
What is excitation energy?
The energy required to move an electron from it’s ground state to it’s excitation state.
What is excitation potential?
The potential difference required to move an electron from its ground state to the excited state.
What are first and second excitation potentials for a hydrogen atom?
10.2 eV and 12.1 eV.
What is the ionization energy for hydrogen atom?
13.6 eV.
What is the De Broglie wavelength formula?
λ= h = h
p mv
What does De Broglie’s hypothesis state?
All matter has wave-like properties, with wavelength inversely proportional to momentum.
What condition must be met for an electron wave to exist in a stable orbit?
2πr=nλ
What is the Bohr quantization condition derived from De Broglie theory?
mvr= 2π where n is a positive integer.
nh
What are X-rays?
Electromagnetic waves with wavelengths in the range of an Angstrom.
How are X-rays produced?
When high-speed electrons strike a metal target, converting kinetic energy into X-ray photons.
