H2O is liquid and H2S is a gas becausea)oxygen forms stronger hydrogen level than sulphur.b)oxygen is less electronegative than sulphur.c)atomic radius of oxygen is less than that of sulphur.d)atomic radius of oxygen is greater than that of sulphur.Correct answer is option 'A'. Can you explain this answer?

Question

Answer

In h2o there is hydrogen bonding because oxygen has a high electronegativity(only second to flourine). so, the hydrogen atoms from other molecules of water forms a hydrogen bonds with oxygen resulting in intermolecular hydrogen bonding. ... therefore at room temperature h2o is aliquid and h2s is a gas.

Answer

H₂O has intermolecular hydrogen bond between its molecules (H—O—H------H—O—H) while H₂S has weak Van der Waals forces between its molecules. Hence the molecules of H₂O are strongly packed than H₂S, thus water is at liquid state at room temperature

Answer

Comparison of H2O and H2S States
The difference in the physical states of water (H2O) and hydrogen sulfide (H2S) is primarily due to the strength of intermolecular forces. Here are the key points explaining why H2O is a liquid while H2S is a gas:
Hydrogen Bonding in H2O
- Water molecules exhibit strong hydrogen bonding due to the highly electronegative oxygen atom.
- Each water molecule can form up to four hydrogen bonds with neighboring molecules, creating a robust network that stabilizes the liquid state.
Weak Intermolecular Forces in H2S
- In contrast, H2S has sulfur, which is less electronegative than oxygen.
- The weaker dipole-dipole interactions and London dispersion forces in H2S result in lower intermolecular attraction, allowing it to exist as a gas at room temperature.
Electronegativity and Molecular Polarity
- Oxygen's higher electronegativity compared to sulfur leads to a more polar O-H bond in H2O.
- This polarity enhances the strength of hydrogen bonding, unlike in H2S, where the bonds are less polar and do not facilitate strong interactions.
Atomic Radius Consideration
- Although oxygen has a smaller atomic radius than sulfur, this primarily affects bond length rather than the nature of bonding.
- The key factor is the ability of oxygen to form strong hydrogen bonds, not just the size of the atoms.
Conclusion
- The superior hydrogen bonding in H2O compared to the weaker interactions in H2S is the primary reason for the difference in their physical states.
- Thus, the correct answer is option 'A': oxygen forms stronger hydrogen bonds than sulfur, leading to water being a liquid and hydrogen sulfide being a gas.

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