Answer:
B. Lower than 100 °C because hydrogen sulfide has dipole-dipole interactions instead of hydrogen bonding.
Explanation:
Intermolecular bonds exists between seperate molecules or units. Their relative strength determines many physical properties of substances like state of matter, solubility of water, boiling point, volatility, viscosity etc. Examples are Van der waals forces, hydrogen bonds and crystal lattice forces.
In hydrogen sulfide, the intermolecular bond is a dipole-dipole attraction which is a type of van der waals attraction. It occurs as an attraction between polar molecules. These molecules line such that the positive pole of one molecule attracts the negative pole of another.
In water, the intermolecular bond is hydrogen bonds in which an electrostatic attraction exists between the hydrogen atom of one molecule and the electronegative atom of a neighbouring molecule.
Based on their relative strength:
Van der Waals forces < Hydrogen bonding forces < crystal lattice
This makes water boil at a higher temperature than hydrogen sulfide.
Answer:
Ice floats on water because it is less dense than water. When water freezes into its solid form, its molecules are able to form more stable hydrogen bonds locking them into positions. Because the molecules are not moving, they're not able to form as many hydrogen bonds with other water molecules. Ice is a unique substance because it is solid-state — ice — is less dense than its liquid state. Because of this property, ice floats in water. Physical properties are characteristics of a substance. They do not change. Ice floats on water because it is less dense than water. When water freezes into its solid form, its molecules are able to form more stable hydrogen bonds locking them into positions.
<span>If a neutral atom becomes negatively charged, it has undergone reduction.
Reduction is the process through which a neutral atom gain an electron (thus reducing its oxidation number) and turns into a negative ion (also known as : anion)</span>
Again, I believe the answer would be D. seawater.