Atomic structure, isotopes and relative mass and Formulae+Equations Flashcards
Atomic structure, isotopes and relative mass and Formulae+Equations.
What is the relative mass of proton-neutron and electron?
Proton- 1
Neutron- 1
Electron- 1/1836
Define the term isotope:
An atom of the same element with different numbers of neutrons but the same number of protons and electrons.
What does the notation A mean?
number of protons and number of neutrons
What does the notation Z mean?
number of protons
What are cations?
Positive ions.
What are anions?
Negative ions.
Define the term relative isotopic mass.
The mass of an isotope relative to 1/12th the mass of an atom of carbon-12.
Define the term relative atomic mass
The weighted mean mass of an atom relative to 1/12th the mass of an atom of Carbon-12.
How are the percentage abundances of isotopes in a sample of an element found?
Using a mass spectrometer.
How does a mass spectrometer work?
The sample is placed.
The sample is vaporised and then ionised to form positive ions.
The ions are accelerated.
Heavier ions move more slowly and are more difficult to deflect than lighter ions, so the ions of each isotope are separated.
The ions are detected on a mass spectrum as a mass to charge ratio.
Each ion reaching the detector adds to the signal, so the greater the abundance the larger the signal.
What is the formulae for nitrate ion?
NO(3) -
What is the formulae for carbonate ion?
CO(3) 2-
What is the formulae for sulfate ion?
SO(4) 2-
What is the formulae for hydroxide ion?
OH-
What is the formulae for ammonium ion?
NH(4) +
