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Flashcards in 2 amount of substance Deck (14):
1

relative atomic mass

the weighted average mass of an atom of an element, taking into account its naturally occurring isotopes, relative to 1/12 the relative atomic mass of an atom of carbon-12 (atom)

2

relative molecular mass

the mass of that molecule compared to 1/12 the relative atomic mass of an atom of carbon-12 (molecule)

3

relative formula mass

the average mass of an entity compared to 1/12 the relative atomic mass of an atom of carbon-12

[add up relative atomic masses of all atoms in the molecule]
(for ionic compounds because they don't exist as molecules)

4

entities

general word for particle, can be atom/molecule/ion/electron/simplest formula unit of giant ionc structure e.g. NaCl

5

avogadro constant/number

the total number of particles in a mole of substance - 6.022x10^23 - the number of atoms in 12g of carbon-12

6

mole

a quantity of a substance that contains the avogadro number of particles (e.g. atoms, molecules or ions)

7

molar mass

the mass per mole of a substance in kg/mol or g/mol (which is Mr)

8

solution

= solvent + solute dissolved in it

9

empirical formula

the simplest whole number ratio of atoms of each element in a compound

10

molecular formula

the actual number of atoms of each element in a compound

11

stoichiometry

the simple whole number ratios in which chemical species react and are produced

12

spectator ions

ions that are unchanged during a chemical reaction, they take no part in the reaction

13

atom economy

the efficiency of a chemical reaction by comparing the total number of atoms in the product with the total number of atoms in the starting materials [theoretical]

14

percentage yield

in a chemical reaction, this is the actual amount of product produced divided by the theoretical amount (predicted from the chemical equation) expressed as a percentage [practical]