1.4 - Counting Particles by Mass: The Mole Flashcards
State Avogadro’s Number to 3 significant figures.
6.02*10^23
What is relative atomic mass? (Ar)
The weighted average mass of the naturally occurring isotopes of an element relative to 1/12 of the mass of an atom of carbon-12
What is relative molecular mass? (Mr)
The weighted average mass of a molecule relative to 1/12 of the mass of an atom of carbon-12
It is the sum of the Ar of the atoms in the molecule.
State the equation relating mass, molar mass and amount of substance.
State the percentage composition equation.
What is the empirical formula of a compound?
The simplest ratio if atoms of each element present in that compound.
What is the molecular formula of a compound?
The number of atoms of each element actually present in a molecule.
What are the three ways to measure concentration? List out their formulas too.
State Avogadro’s law.
The volume occupied by a gas is directly proportional to the amount in mol of gas. At constant temperature and pressure.
Under what conditions can mole ratios be treated as volume ratios?
Under fixed temperature and pressure.
