Definitions [10]
Chemistry is the branch of science that deals with the identification of substances, the matter they are composed of, and the investigation of their properties.
Define relative atomic mass.
Relative atomic mass is defined as the ratio of the average atomic mass to the unified atomic mass unit.
Relative atomic mass (Ar) = `"Average mass of the atom"/"Unified atomic mass"`
Define the term Relative atomic mass.
"The relative atomic mass or atomic weight of an element is the number of times one atom of the element is heavier than `1/12` times of the mass of an atom of carbon - 12".
Relative atomic mass = Mass of 1 atom of the element `1/12` of the mass of one C12 atom.
Define the term:
Mole
Mole is the amount of a substance containing elementary particles like atoms, molecules or ions in 12 g of carbon - 12.
Define the term.
Molar volume
One mole of any gaseous molecules occupies 22.4 dm3 (litre) or 22400 cm3 (ml) at standard temperature and pressure (STP). This volume is known as the molar volume.
Define the term:
Relative molecular mass
The relative molecular mass of a compound is the number that represents how many times one molecule of the substance is heavier than `1/12` of the mass of an atom of carbon 6C12.
Define the term:
Gram atom
The quantity of the element which weighs equal to its gram atomic mass is called one gram atom of that element.
A mole is the amount of pure substance containing the same number of chemical units as there are atoms in exactly 12 grams of carbon -12.
Avogadro's number is defined as the number of atoms present in 12 g (gram atomic mass) of C-12 isotope, i.e., 6·022 x 1023 atoms.
OR
Avogadro's number is the number of elementary units, i.e., atoms, ions or molecules present in one mole of a substance. It is denoted by NA.
Define the term:
Avogadro’s number
Avogadro’s number is defined as the number of atoms present in 12g of 6C12 isotope i.e. 6.023 × 1023 atoms.
