Mass = number of mol x molar mass
Mass = 0.28mol x 55.8g/mol
Mass = 15.624g
Answer:
Pencil is an element and a heterogeneous mixture
Explanation:
A substance either an ion or a molecule that can act either an acid or a base depending on a medium is called Amphoteric. Some metals like zinc, tin, copper and aluminium which produce either metal oxides or hydroxides are examples of amphoteric. During the Amphoterism, the metal compound acts either an acid or a base depending on their oxidation state.