Question

Fill in the following blanks :
(a) 1 mole contains ...................... atoms, molecules or ions of a substance.
(b) A mole represents an ..................... number of particles of a substance.
(c) 60 g of carbon element are ................... moles of carbon atoms.
(d) 0.5 mole of calcium element has a mass of ......................
(e) 64 g of oxygen gas contains ....................... moles of oxygen atoms.

Answer 1

(a) 1 mole contains 6.022 × 10²³ atoms, molecules or ions of a substance.
(b) A mole represents the Avogadro number of particles of a substance.
(c) 60g of carbon element are 5 moles of carbon atoms.
(d) 0.5 moles of calcium element have a mass of 20g.
(e) 64g of oxygen contain 4 moles of oxygen atoms.