Question

The Chemical Formula For Sodium And Sulphur Contains

• A. One Sulphur And One Sodium Atoms.
• B. One Sulphur And Two Sodium Atoms.
• C. Two Sulphur And One Sodium Atoms
• D. Two Sulphur And Two Sodium Atoms.

Answer 1

The correct option is B

One Sulphur And Two Sodium Atoms.

Explanation for correct answer:-

Option (B) One Sulphur And Two Sodium Atoms:

• The chemical formula of a compound can be defined as the symbolic representation of its chemical composition.
• The atomic number of Sodium is 11 and its electronic configuration is $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^1$
• The atomic number of Sulphur is 16 and its electronic configuration is $1{\mathrm{s}}^{2}2{\mathrm{s}}^{2}2{\mathrm{p}}^{6}3{\mathrm{s}}^{2}3{\mathrm{p}}^4$
• Thus according to the octet rule we know that Sodium needs to lose 1 electron then its outermost shell would have 8 electrons which would make it stable.
• The same thing happens with Sulphur, it has 6 electrons in its outermost shell.
• Thus it needs two more electrons to complete the octet state and be stable.
• Therefore, 2 Sodium atoms donate 1 electron each to 1 Sulphur atom.
• Thus the name of the compound becomes Sodium sulphide and the chemical formula becomes ${\mathrm{Na}}_2\mathrm{S}$.
• Hence it is the correct option.

Explanation for incorrect answer:-

Option (A) One Sulphur And One Sodium Atoms:

• According to this, one Sodium reacts with 1 Sulphur atom.
• This gives us the chemical formula $\mathrm{NaS}$, which is not possible.
• Hence it is the incorrect option.

option (C) Two Sulphur And One Sodium Atoms:

• According to this, one Sodium reacts with 2 Sulphur atoms.
• This gives us the chemical formula ${\mathrm{NaS}}_2$, which is not possible.
• Hence it is the incorrect option.

Option (D) Two Sulphur And Two Sodium Atoms:

• According to this, 2 Sodium reacts with 2 Sulphur atom.
• This gives us the chemical formula ${\mathrm{Na}}_2{\mathrm{S}}_2$, which is not possible.
• Hence it is the incorrect option.

Therefore, the chemical formula for Sodium and Sulphur contains ${\mathrm{Na}}_2\mathrm{S}$(Sodium sulphide)