Answer:
The compound contains an Ca²⁺ ion and 2 OH⁻ ions ( this last ion is a polyatomic anion) These ions are held together by ionic bonds. OH- consists of oxygen and hydrogen ions bonded by a covalent bond
Explanation:
The covalent bond is the chemical bond between atoms where electrons are shared, forming a molecule. Covalent bonds are established between non-metallic elements, such as hydrogen H, oxygen O and chlorine Cl. These elements have many electrons in their outermost level (valence electrons) and have a tendency to gain electrons to acquire the stability of the electronic structure of noble gas and complete their valence layer.
An ionic bond is produced between metallic and non-metallic atoms, where electrons are completely transferred from one atom to another. During this process, one atom loses electrons and another one gains them, forming ions. Usually, the metal gives up its electrons forming a cation to the nonmetal element, which forms an anion. In this way, the octet rule is fulfilled, which establishes that the atoms of the elements bind each other in the attempt to complete their valence layer, leaving the atom stable with 8 electrons in its last layer.
Finally, a polyatomic anion is a group of two or more atoms that are chemically bonded and have a negative charge. They are considered as a unit in chemical reactions. Generalemte in this type of anions the electrons are shared by all the atoms of the polyatomic ion. Then a covalent bond is established. One of the most common polycation anions is the hydroxyl ion (OH-).
So, in this case, the compound contains an Ca²⁺ ion and 2 OH⁻ ions ( this last ion is a polyatomic anion) These ions are held together by ionic bonds. OH- consists of oxygen and hydrogen ions bonded by a covalent bond because it is a polyatomic where electrons are shared. And as previously mentioned, its negative charge means that the group of atoms has gained electrons.
