Select ALL answers that are true for K2S:
a) Ionic bond
b) Covalent bond
c) Named potassium sulfide
d) Named dipotassium monosulfide
e) Named potassium disulfide
The Correct Answer and Explanation is :
The correct answers for K2S are:
a) Ionic bond
c) Named potassium sulfide
d) Named dipotassium monosulfide
Explanation:
1. Ionic Bond (a)
K2S, or potassium sulfide, is formed from potassium (K) and sulfur (S). Potassium is a metal that tends to lose one electron, forming a potassium ion (K⁺), while sulfur is a non-metal that tends to gain two electrons to form a sulfide ion (S²⁻). The transfer of electrons from potassium to sulfur creates an ionic bond due to the electrostatic attraction between the positively charged potassium ions and the negatively charged sulfide ions. This characteristic of forming ionic compounds is typical for metals and non-metals.
2. Named Potassium Sulfide (c)
The compound K2S is commonly known as potassium sulfide. The name reflects the ions present in the compound: two potassium ions (K⁺) and one sulfide ion (S²⁻). In nomenclature, the name of the metal (potassium) is followed by the name of the non-metal with an “-ide” suffix, which in this case, comes from sulfur.
3. Named Dipotassium Monosulfide (d)
In more systematic nomenclature, K2S can also be named dipotassium monosulfide. This name indicates that there are two potassium ions (di-) and one sulfide ion (mono-). Although this naming convention is less commonly used, it follows the IUPAC rules for naming compounds based on the number of each type of ion present.
Incorrect Options:
- b) Covalent bond: K2S does not exhibit covalent bonding because it involves the transfer of electrons rather than sharing them, typical of ionic bonds.
- e) Named potassium disulfide: This name is incorrect because it would imply the presence of two sulfide ions, which is not the case here; K2S contains only one sulfide ion.
In summary, K2S is a compound characterized by ionic bonding, and its systematic names include potassium sulfide and dipotassium monosulfide, reflecting its composition accurately.