Mass number and isotopes Flashcards
What are isotopes?
Atoms of an element that have the same number of protons and electrons but different number of neutrons
Why do isotopes have the same chemical properties?
Because they have the same electron configuration
What is atomic mass?
The number of protons and neutrons added together
What is atomic number?
The number of protons (the same as electrons)
What is a mass spectrometer used for?
It can measure the mass of molecules within an unknown substance
What are the four steps of mass spectroscopy?
Ionisation, acceleration, drift and detection
How are atoms or molecules ionised for mass spectroscopy?
Electron impact or electrospray
How does electron impact ionise an atoms/molecule
The sample is vaporised and bombarded by high energy electrons
What is the equation for electron impact?
X(g) -> X^+(g) + e^-
What is the equation for electrospray?
X(g) -> XH^+(g)