Atom And Redox Flashcards
Relative mass of an electron
1/2000
Relative isotopic mass -
Mass of an isotope compared with 1/12 of the mass of carbon 12
Relative atomic mass -
Weighted mean mass of an atom of an element compared with 1/12 of the mass of carbon 12
What is z the symbol for ?
Charge
What is an ion ?
A charged atom / group of atoms due to unequal number of protons and neutrons
What are the 3 main factors of nuclear attraction ?
Atomic radius
Shielding (no. of inner shells)
Nuclear charge
As the nuclear attraction decreases…
The ionisation energy decreases
What is an orbital?
Region which can hold up to 2 electrons with opposite spins
What is a sub shell ?
Made up of orbitals
E.g. s / p / d
why is second ionisation energy always greater than the first ?
electrons pull closer to nucleus as more are removed, meaning more energy is needed to remove them
what is the no. of orbitals with d shell ?
5 (so 10 electrons)
what is the no. of orbitals with f shell ?
7 (so 14 electrons)
oxidation no. of uncombined elements
0
e.g. H² is 0
oxidation no. of simple ions
the charge of the ion
e.g. I- is 1-
oxidation no. of (combined) fluorine
-1
oxidation no. of (combined) oxygen
-2 exc with hydrogen peroxide it is -1
oxidation no. of (combined) hydrogen
+1 exc in hydrides it is -1
e.g. LiH , H is -1
oxidation no. of (combined) group 1 metals
+1
oxidation no. of (combined) group 2 metals
+2
the sum of oxidation no. in a compound =
the charge
what is the nucleon number ?
mass number
define isotope
atoms with same no of protons, diff no of neutrons
given the no. of particles, how do you find no. of moles …
no. of particles / Avogadro’s number
what is Avogadro’s number?
6.02x10^23
what is molar mass measured in ?
g mol ^-1
how to work out no. of atoms in something ?
work out moles x by Avogadro’s number, then x by no. of atoms in molecule
acid + base =
salt + water
define acid
produces H+ ions in aqueous solutions
what is symbol for oxidizing agent ?
[O]
atom economy =
Mr of useful products / Mr of all products
what do the roman numerals show ?
oxidation number (of the metal)
