electromagnetic and atomic spectrum 1.1 Flashcards
avogadros constant
6.02 x 10^23
what is avogadros constant
the amount of molecules in a mole
what is electromagnetic radiation
a form of energy and consists of waves that can travel in a vacuum at a constant velocity (c)
high frequency =
short wavelength
low frequency =
long wavelength
velocity
speed of light 3 x 10^8
wavelength
the distance between adjacent crests or troughs of a wave
frequency
the number of wavelengths that pass a fixed point in one second
electromagnetic spectrum
the range of frequencies or wavelengths of electromagnetic radiation
wave particles duality theory
when EM radiation energy can be described as a wave but also behave as a particle when it is emitted or absorbed
photons
particles of energy that have a definite size and a definite energy value (quanta)
excited state
when an electron absorbs energy it can move to a higher energy level
ground state
this is the lowest possible electronic configuration the electrons in an atom can adopt
what happens when electrons move down to ground state
energy is given out
what does the photons energy depend on
where it is falling from or to
when the photon energy changes what else changes
frequency, wavelength and colour
what proves the existence of different energy levels in an atom
different elements having their own unique spectra
what’s used to split white light
prisms which split the light into a rainbow
when are emissions a series of discrete wavelengths
when the light source is from a chemical being heated
atomic emission spectra
when energy is given out from elements
atomic absorption spectra
when white light is directed through a gaseous sample of an element, some of the energy is absorbed by the element’s electrons, the radiation that emerges have certain wavelengths missing and this shows up as dark lines on a continuous spectrum
what’s used to quantify a sample
spectra
what is concentration related to
the absorption/ emission intensity
what to use to work out an unknown concentration
use a calibration curve with a known concentration and is useful for metal concentrations in drinking water and food
increase of energy in order of decreasing wavelength
radio waves, microwaves, infrared, visible, ultraviolet, x rays and gamma rays
