Atomic Structure Flashcards
What subatomic particles are found in every atom?
- Protons
- Neutron
- Electrons
How big is an atom and how big is its nucleus?
0.1 nm
the nucleus is 1/10,000 of the atom
Where are the subatomic particles found in the atom?
- Protons and Neutrons found in the nucleus
- Electrons orbit the nucleus on energy levels/ shells
What are the relative masses of the subatomic particles?
Proton = 1 Neutron = 1 Electron = negligible/ very small
What are the relative charges of the subatomic particles?
Proton = +1 Neutron = neutral/ 0 Electron = -1
What is the charge of the nucleus?
Positive
What is the charge of the overall atom? why?
Neutral:
-The positive charge of the nucleus and the negative charges of the electrons balance out
What is the relationship between the No. of Electrons and the No. of Protons?
They are equal
What are ions?
Electrically charged particles formed from neutral atoms gaining or losing electrons
What happens when an atom loses electrons?
- There will be more protons than electrons in the atom
- Charges are no longer balanced
- Positively charged ions form
What happens when an atom gains electrons?
- There will be more electrons than protons in the atom
- Charges are no longer balanced
- Negatively charged ions form
What is the mass number of an atom? Where is it written on atoms shown on the periodic table?
The total number of protons and neutrons in an atom
it is the bigger number usually on the TOP
What is the atomic number of an atom? Where is it written on atoms shown on the periodic table?
The number of Protons ONLY in an atom
it is the smaller number usually on the BOTTOM
What happens to an atom during chemical reactions?
-Involves the gain/ lose of electrons
do not involve the nucleus, so the number of protons does not change
What is meant by the term electron configuration?
A description of how the electrons are arranged around the nucleus in an atom
How are electrons removed from an atom?
-Removal of electrons happen one-by-one, starting from the outermost electrons
What are isotopes?
Atoms of an element with the same number of protons, but different number of neutrons/
They have a different mass number
What is a mass spectrum used for?
To find the number and abundances of isotopes of an element
What is shown on a mass spectrum?
- the m/z ration of ions is displayed on the x-axis (assuming the charge of every ion is +1 the m/z ratio is equal to the mass of the ion)
- the y-axis gives information on the number of ions/ abundance of any particular m/z value detected
- each peak indicates a new species
What is the relative atomic mass of an element?
The weighed mean of the mass numbers of the isotopes of an element
What are the 2 formulae for R.A.M?
R.A.M = [SUM OF (Isotopic mass x abundance)] / 100
OR
R.A.M = [SUM OF (Isotopic mass x relative abundance] / [Total Abundance]
