2.1.3 Amounts Of Substances Flashcards
What does Avogadro’s Constant represent (2 points)
The n.o atoms in the mole of a substance, n.o of atoms in 12g of carbon 12.
Avagadro’s number
6.02x10^23
Relative atomic mass definition (3 points)
Weighted mean mass of a atom compared with 1/12 the mass of an atom of carbon 12
Relative isotopic mass definition (2 points)
Mass of an isotope relative to 1/12 of the mass of a carbon 12 atom
Empirical formula definition (3 points)
The simplest whole number ratio of atoms (of each element) present in a compound
Relative formula mass definition (2 points)
Combined atomic masses , of elements in a compound
Hydrated salt definition (2 points)
Crystalline salt loosely attached to a certain number of water molecules
Dehydration definition
The removal of water of crystallisation
Anhydrous substance definition
Contains no water of crystallisation
Standard solution definition
A solution with a known concentration
Avogadro’s law
Equal volumes of different gasses at the same temperature and pressure will contain the same number of particles
What are standard conditions
298K 100KPa
What is the ideal gas equation and what does everything represent
pV=nRT
p = pressure in Pa, V= volume in m^3 n=number of moles. R= gas constant. T= temperature in Kelvin
What is the gas constant
8.314JK-1mol^-1
Percentage Yield definition (2 point)
How much product was made in comparison to expected(calculated)
amount
Theoretical yield definition
Maximum mass of product expected via calculations from reactant masses
Actual yield definition
The real obtained mass measured of product after a reaction
Percentage yield equation
Percentage yield = (actual/theoretical)x100
Atom economy definition
measure of mass of desired product compared to mass of all reactants
atom economy calculation
mass/mr of desired product x 100 / total mass/mr of product
equation to find moles
mol=mass(g)/mr
concentration equation
Conc = mass/vol
Molarity equation
mol/dm^3
volume in dm^3 that a mole of gas takes up
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