2.1.1 Atomic Structure And Isotopes Flashcards
What charge is a proton?
+1
What charge is a proton?
+1
What charge is a neutron?
0 (neutral)
What charge is an electron?
-1
What is the mass of an electron?
1/1836
What is the mass number?
Protons + Neutrons
What is the atomic number?
Protons
Where are protons found?
In the nucleus
Where are neutrons found?
In the nucleus
Where are electrons found?
Arranged around the nucleus in shells.
What are isotopes?
Atoms of the same element with different number of neutrons and masses. (Same number of protons)
What is an ion?
A charged atom, with different numbers of electrons and protons.
What is relative atomic mass?
The weighted mean mass of an atom of an element relative to 1/12th if the mass of a carbon-12 atom.
What is relative isotopic mass?
The weighted mean mass of an isotope relative to 1/12th of the mass of a carbon-12 atom.
How does a mass spectrometer work?
The sample is vapourised
The sample is ionised to form positive ions
The ions are accelerated
Heavy ions move slower / are less deflected
The ions are detected as a mass-to-charge ratio, written as m/z
Each ion produces a signal, so the larger the signal, the greater the abundance.
How can relative atomic mass of an element and its isotopes be found?
Using a mass spectrometer . Percentage abundance × m/z
Why can we assume m/z = mass , in mass spectrometry?
Most of the time, only one electron is lost in ionisation of the sample.
What is the history of the atom?
John Dalton - spheres
Jj Thompson - plum pudding
Ernest Rutherford - gold leaf
Niels Bohr - fixed energy shells
