Mass Relationships in Chemical Reactions Practice QuestionsG

Atomic mass mass of an atom in atomic mass units An atomic mass unit is equal to? One twelth the mass of one carbon-12 atom The average atomic mass is equal to? atomic mass on the periodic table Isotopes are atoms of the same element with a different number of ___ and so they have different ___ 1) neutron 2) masses Mole Is a counter and relates to mass.* It is similar to a dozen. *It can count the number atoms/molecules/particles. Molar Mass *is the mass of one mole of the substance. *g/mol = atomic mass of the element *molar mass of an element contains mols of atoms Avogadro's number particles/atoms/molecueles > moles *6.022x10^23 Percent Composition Mass of element/ mass of compound x 100 Tell how much an element contributes to the mass of the compound