Question

A geologist tests a rock containing calcium oxide by reacting it with hydrochloric acid. Water and calcium chloride form. Which bonds break?

H–O bonds in water and Ca–Cl bonds in calcium chloride
Ca–Cl bonds in calcium chloride and H–Cl bonds in hydrochloric acid
Ca–O bonds in calcium oxide and H–O bonds in water
Ca–O bonds in calcium oxide and H–Cl bonds in hydrochloric acid

Answer 1

The following bonds breaks:

Ca–O bonds in calcium oxide and H–Cl bonds in hydrochloric acid

Step-by-step explanation:

When calcium oxide reacts with hydrochloric acid, water and calcium chloride are formed. The reaction is given as:

CaO + 2HCl ⇒ CaCl₂ + H₂O

Where

CaO has an ionic bond between Ca and O because Ca is a metal and O is a non-metal, which results in complete transfer of electrons from calcium to oxygen.

HCL is usually in a gaseous state which has a covalent bond between H and Cl, but HCL acid means HCL in the presence of water, which will have an ionic bond.

Under the given reation, both of these ionic bonds break to form new ones