Question

Which option contains an example of a polyatomic ion? O MgCl O NH₄ O KNO₃ O CaCl₂

Answer 1

NH₄, the ammonium ion, is an example of a polyatomic ion. Polyatomic ions are charged entities with two or more covalently bonded atoms or metal complexes acting as single units.

Step-by-step explanation:

The option that contains an example of a polyatomic ion is NH₄ which is the ammonium ion. A polyatomic ion is a charged entity composed of two or more atoms covalently bonded or of a metal complex that can be considered to be acting as a single unit. The ammonium ion is a common example of a polyatomic cation, which carries a positive charge. Other examples of polyatomic anions include sulfate (SO₄²⁻), nitrate (NO₃⁻), and carbonate (CO₃²⁻).

Answer 2

The option containing an example of a polyatomic ion is NH₄ or ammonium ion. Polyatomic ions are charged species composed of two or more covalently bonded atoms acting as a unit, and they are used as discrete units in naming ionic compounds.

Step-by-step explanation:

A polyatomic ion is a charged chemical species (ion) composed of two or more atoms covalently bonded, which can be considered to be acting as a single unit. The charge on this group of atoms is due to the presence of an excess or deficiency of electrons. When naming ionic compounds that include polyatomic ions, we often treat these ions as indivisible units, and the overall charge must be balanced between the cations and anions in the compound.

Among the options given, the example of a polyatomic ion is NH4+ or ammonium ion. The other options listed, such as MgCl2 (magnesium chloride), KNO3 (potassium nitrate), and CaCl2 (calcium chloride), contain only monatomic ions or simple ions.

The formula for a compound with a polyatomic ion might require parentheses if there are multiple polyatomic ions within one formula unit. For example, calcium nitrate is written as Ca(NO3)2, indicating two nitrate ions for each calcium ion.