1.1-1.12 Flashcards
define isotope
atoms of the same element with the same number of protons but a different number of neutrons
define relative isotopic mass
the mass of a single isotope of and element relative to 1/12 the mass of 1 atom of carbon 12
define relative atomic mass
the average mass of an atom of an element relative to 1/12 the mass of one atom of carbon 12
what is mass spectrometry
an accurate way of measuring the mass of atoms and molecules
define relative molecular mass
the average mass of a molecule compared to 1/12 the mass of one atom of carbon 12
define Avogadro’s constant
the number of atoms or molecules in one mole of a substance
what is an empirical formula
the simplest whole number ration of elements in a compound.
which transition metals only have one possible charge
silver- Ag^+
zinc- Zn^2+
what is a salt
an ionic compound formed when an acid reacts with a base
what is the water of crystallisation
the water molecules contained withing hydrated salts. this can be removed using heat to get anhydrous salt compounds
how is a hydrated salt turned into an anhydrous salt
by heating the hydrated salt to constant mass.
how is the degree of hydration determined?
from the mass of the hydrated salt before and after heating to constant mass. form this the mass of water is calculated, the moles of the salt and water is calculated, then the molar ratio gives you the number of water molecules per salt molecule in the hydrated salt
what is concentration
the amount of solute in a given volume of solvent
what is the limiting reagent
the reactant that is not in excess that will be used up first, stopping the reaction
what is Avogadro’s law
at the same temperature and pressure, one mole of any gas has equal volumes
