Chapter 2 Atoms Ions And Compounds Flashcards
What are the relative masses and charges of the three subatomic particles
Proton 1,1+
Neutron 1,0
Electron 1/1836, 1-
Where is nearly all the mass of the atom contained
In the nucleus
Every atom of the same element has….
The same number of protons
Isotopes of the same element have…
Different masses
The same number of protons and electrons
Different number of neutrons in the nucleus
Definition of atomic number
The number of protons in the nucleus of an atom
Define mass number
The number of particles (p+n) in the nucleus
Define isotope
Atoms of the same element with different numbers of neutrons
Do isotopes differ in chemical reactions
No as chemical reactions involve the electrons and isotopes have the same number of electrons
Are there differences in physical properties in isotopes
Higher mass isotopes will have higher boiling and melting points and higher density
What is a cation
A positive ion
What is an anion
A negative ion
Define ion
A positively or negatively charged atom or a covalently bonded group of atoms (molecular ion)
Define relative isotopic mass
The mass of an atom of an isotope relative to one-twelfth of the mass of an atom of carbon 12
For an isotope the relative isotopic mass is the same as the mass number
Define relative atomic mass Ar
The weighted mean mass of an atom of an element relative to one-twelfth of the mass of an atom of carbon 12
The combination of the contribution to the overall mass the different isotopes make
How does a mass spectrometer work
1) place sample in the mass spectrometer
2) the sample is vaporised and ionised ( bombarded with electrons to knock off electrons and make it a positive ion) to form positive ions
3 )the ions are accelerated in a magnetic field, the heavier ions move slower and are deflected less
4) the ions are detected as a mass to charge ratio (m/z)
