Atomic structure and shape Flashcards
Electromagnetic radiation features
Behaves like a wave
Travels at the speed of light
Has variable frequency and wavelength
Variables of electromagnetic radiation
Frequency and wavelength - since speed of light is constant
Wavelength and frequency formula of electromagnetic spectrum
C= F(lambda)
C is the speed of light (3.00x10^8)
F is the frequency (S-1)
Lambda is wavelength (m)
Order of electromagnetic radiation largest to smallest wavelength
Radio waves
Micro waves
Infrared radiation
Visible light
Ultraviolet light
X- ray
Gamma ray
Rules of electromagnetic radiation in terms of frequency and wavelength
High frequency has short wavelength
Low frequency has long wavelength
Order of electromagnetic radiation from highest to lowest frequency
Gamma ray
X ray
Ultraviolet light
Visible light
Infrared radiation
Microwaves
Radio waves
Two types of electromagnetic radiation behaviour
Waves and particles
Photons definition
Electromagnetic radiation which behave like particles and are packets of energy.
What happens when a photon is emitted
Energy is lost by electrons and electrons are transferred back to their ground state energy shell.
Energy of a single photon equation
E= hf
Energy = planck’s constant x frequency
Plancks constant value
6.63x10^-34
Energy of one mole of photons equation
E = Lhf/1000
Energy = avogadros constant x plancks constant x frequency /1000
The Avogadro constant value
6.02 x 10^23
Rule for distinguishing between avogadros and plancks constant equations
If it says kJ mol-1 it’s avogadros
If it says joules it’s plancks
Avogadros constant definition
The number of species in one mole
Rule of frequency and energy emitted by a photon
The higher the frequency the higher the energy transmitted by the photon
Practical avogadros constant question
Use c = f lambda
Use E= Lhf/1000
How is energy lost from promoted electrons
A photon is emitted
Characteristics of photons being emitted
A specificwavelength of light will be emmited whoch is associated woth the enegy gap
The spectrum is made up of discrete lines
Each element will produce a unique patters when photons are emitted
Importance of electrons emitting photons
It provides direct evidence that electron energy shells exist.
What is the use of atomic emission and absorption spectroscopy
To identify and quantify the elements in a sample
Continuous spectrum colours
Red yellow green blue
Atomic absorption spectroscopy characteristics
Electromagnetic radiation of changing wavelength directed at an atomised sample
Radiation of specific wavelengths is absorbed as electrons are promoted to higher energy levels
This causes a decrease in the transmission of specific wavelengths and black lines.
Rules of elements and spectroscopy
Each element produces a unique absorption and emission spectroscopy.
The higher the concentration of an element the higher the intensity of light emitted.
Difference between light emitted and transmitted
Light is emitted in emission spectroscopy and transmitted in absorption spectroscopy.
Transmission means pass through
Emission means produced