Question
Question: In sodium sulphide, the corresponding cation and anion attain the stable electronic configurations o...
In sodium sulphide, the corresponding cation and anion attain the stable electronic configurations of _____ and _____ respectively.
A.Ne and Ar
B.Ne and Kr
C.Ar and Ne
D.Kr and Ne
Solution
As we know that a cation has more protons than electrons consequently giving it a net positive charge whereas an anion has more electrons than proton and thus consequently giving it a net positive charge. Sodium sulphide is a salt which plays an essential role in the organic chemistry industry. The formula for sodium sulphide is Na2S,or more commonly its hydrate Na2S.9H2O.
Complete step by step answer:
We must remember that the sodium sulphide is an ionic compound or sulphide salt with formula Na2S. It is a yellow to brick red fused solid or crystalline solid. It has odour of rotten eggs. If it is exposed to moist air it becomes liable to spontaneous warmth and may cause ignition of nearly combustible material.
Now from the given question,
The cation and anion formed from sodium sulphide are Na+ and S2−.
Now sodium has the atomic number 11 nearly to neon and magnesium, due to cation charge Na+ donates a proton and becomes a completely filled electron, the atomic number of sodium ion becomes 10 which has a similar atomic number with neon. Therefore Na+ and Ne have 10 electrons and thus similar electronic configuration.
Then sulphur has 16 atomic number nearly to argon, due to anion charge S2− gains a proton and becomes completely filled electron so, the atomic number of sulphur becomes 18 which is similar to the atomic number with argon. Therefore S2− and Ar have 18 electrons and thus similar electronic configuration.
Therefore, the option A is correct.
In case of option B, the atomic number of sodium ion and neon is similar but the atomic number of sulphur ion and Kr is different. Therefore, the option B is incorrect.
In case of option C, the atomic number of sodium ion and argon, sulphur ion and neon are differ from each other. Therefore, the option C is incorrect.
In case of option D, the atomic number of sodium ion and Kr, sulphur ion and neon differ from each other. Therefore, the option D is incorrect.
So, the correct answer is Option A.
Note:
Sometimes, we can predict whether an atom will sort a cation or anion based on its position within the periodic table. Alkali metals and alkaline-earth metals always form cations. However, halogens always form anions. Most other non-metals typically form anions (oxygen, nitrogen, sulphur), while most metals form cation (iron, gold, mercury).