The Atom and Redox Flashcards
What is the definition of relative isotopic mass?
THe mass of an atom of a specific isotope of an element relative to 1/12th of the mass of an atom of C12
What is the definition of relative atomic mass?
The weighted mean mass of an element relative to 1/12th the mass of an atom of C12
How is relative atomic mass calculated?
(Percent of sample/100 x Mass of isotope) for all isotopes, added together
What is the definition of relative molar mass?
The weighted mean mass of a molecule, relative to 1/12th the mass of an atom of C12
What is the definition of relative formula mass?
The weighted mean mass of a formula, relative to 1/12th the mass of an atom of C12
What is the definition of 1st ionisation energy?
The energy required to remove one electron from every atom in one mole of gaseous atoms
What is the general formula of a 1st i.e, where X is the element being ionised?
X(g) –> X+(g) + e-
What are the four subshells, in order of smallest to largest?
S,P,D,F
How many electrons can each sub-shell hold? (S-D)
S=2
P=6
D=10
What is redox?
A reaction where an element loses electrons (Oxidation), whilst a different element gains electrons (Reduction)
How many electrons can the first shell hold?
2
How many electrons can shells after the first hold?
8 - But can hold more sometimes
What three factors effect 1st ionisation energy?
- Proton number / Nucleus attraction
- Shielding e-
- Atomic radius
What is the general trend in first ionisation energy across a period?
Generally increasing, decreasing from 2-3 as the electrons enter the p subshell and from 5-6 as electrons start having to share orbitals, slightly repelling eachother.
What is an orbital?
A region of space occupied by up to 2 electrons with opposite spins.
