Atoms and Reactions Flashcards
What is the mass and charge of an electron? Where is it located?
1/2000 and a charge of -1. It’s found in the orbitals.
What is the mass and charge of a proton? Where is it found?
Mass of 1, charge of +1 and it’s found in the nucleus.
What is the mass and charge of a neutron? Where is it found?
Mass of 1, charge of 0 and is found in the nucleus.
What is an ion?
Atoms of the same elements which have the same number of neutrons but a different number of protons and/or electrons.
What is an isotope?
Atoms of the same element with different numbers of neutrons.
What is meant by relative atomic mass (Ar)?
It’s the average mass of an atom of an element on a scale where an atom of carbon-12 is 12.
What is meant by relative isotopic mass?
It is the mass of an atom of an isotope of an element on a scale where an atom of carbon-12 is 12.
What is meant by relative molecular mass?
It is the average mass of a molecule or formula unit on a scale where an atom of carbon-12 is 12.
How do you calculate Ar from isotopic abundance (if the abundance adds up to 100)?
Multiply each relative isotopic mass by its % relative isotopic abundance, and add up the results.
Divide by 100.
How do work out Ar from relative isotopic abundances (from a graph)?
Multiply each relative isotopic mass by its relative isotopic abundance, and add up the results.
Divide by the sum of the isotopic abundances.
What is the definition of a ‘mole’?
Amount of substance, n.
How much is one mole?
6.02 x 10^23, this is avagadros constant.
How do you calculate moles (using Na - avogadros constant)?
no. of n = no. of particles you have / Na
What is molar mass the same as?
Relative molecular mass.
What is an empirical formula?
It gives the smallest whole number ratio of atoms in a compound.
