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How does intermolecular forces of a substance determine the phase the substance is in?
Wiki User
∙ 12y ago
The strength of the intermolecular forces will determine what phase the substance is in at any given temperature and pressure. Consider the halogens for example, fluorine and chlorine are gases, while bromine is a liquid and iodine is a solid at room temperature. When considering the intermolecular forces present, each of these substances only has London forces, which increase in magnitude with increasing size of the molecules, and size increases as you go down a group in the Periodic Table. So, fluorine has the smallest intermolecular forces, and iodine has the largest. This explains why these different substances exist in different phases when at room temperature and pressure. The molecules in fluorine, for example, are only slightly attracted to each other, and therefore the substance exists as a gas. The stronger intermolecular forces in bromine, however, hold the molecules close to each other, but not quite strongly enough to prevent the molecules from sliding past each other; this makes bromine a liquid. Finally, in iodine, the intermolecular forces are actually strong enough that the molecules are held in fixed positions relative to each other, thus making iodine a solid.
Wiki User
∙ 15y ago
Wiki User
∙ 12y agoIf intermolecular forces are stronger, the molecules in the substance are more attracted to each other, and therefore requires more energy to move. Since temperature represents average kinetic energy, and therefore the energy present for the substance to overcome intermolecular forces, substances with stronger intermolecular forces will require a higher temperature to, for instance, melt.
Wiki User
∙ 12y agoThe stronger the intermolecular attractions are between two molecules, the more likely they are to stay together at a any given temperature.
Wiki User
∙ 11y agoThe stronger the inter molecular force, the more energy required to boiling the liquid.
Wiki User
∙ 11y agoheat energy and intermolecular forces cause phase changes.
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The stronger the intermolecular forces in a substance?
The stronger the forces the stronger the attraction between the molecules in the substance. This will tend to increase the temperature of phase changes, melting and boiling points.
Why does temperature no change during energy phase change?
During a phase change, the heat transferred to a substance is used to break intermolecular forces (latent heat), and thus the temperature of the substance does not change. The opposite also occurs: heat is transferred from a substance during a phase change without a decrease in temperature as intermolecular bonds form.
How do the intermolecular forces within a solid differ from that of a gas or liquid How does this explane a solid behavior?
Not exactly sure what you're asking but I'll give it a shot. Intermolecular forces do not change when a substance undergoes a phase change, such as when something goes from a solid to a liquid. The same intermolecular forces that existed when something was a solid still exist when it changes to a liquid, and vice versa. Its just that with the addition of an external factor (most commonly an increase in temperature) a substance is able to overcome the attractive forces in the solid and break apart into a liquid or when a liquid turns into a gas. For when something freezes or condenses the opposite happens, an external factor (most commonly a decrease in temperature) causes a given substance to be attracted to itself more strongly and then the substances comes together as either a liquid or a solid. In summary: The forces do not change. Just how much the forces effect the overall substance changes.
The phase of matter depends on what?
Heat and pressure are the two main factors that determine a substance's current phase.With high heat a substance's phase drifts toward the gaseous phase while freezing temperatures cause it to move toward its solid phase. With pressure it is the opposite. Higher pressures push the substance toward its solid phase, while lower pressures will encourage the substance to evaporate into its gaseous phase.
Why do compounds with strong intermolecular attractive forces have higher boiling points than compounds with weak intermolecular attractive forces?
Heat is simply an expression of how fast molecules are vibrating and moving about, for the purposes of state of matter. Intermolecular bonds are what stop this motion from happening, so the stronger this bond, the higher the temperature needs to be for the compound to melt or boil.
The stronger the intermolecular forces in a substance?
The stronger the forces the stronger the attraction between the molecules in the substance. This will tend to increase the temperature of phase changes, melting and boiling points.
Why does temperature no change during energy phase change?
During a phase change, the heat transferred to a substance is used to break intermolecular forces (latent heat), and thus the temperature of the substance does not change. The opposite also occurs: heat is transferred from a substance during a phase change without a decrease in temperature as intermolecular bonds form.
As heat is added to a substance undergoing a phase change the temperature remains constant because the energy is being used to?
Overcome intermolecular forces
How do the intermolecular forces within a solid differ from that of a gas or liquid How does this explane a solid behavior?
Not exactly sure what you're asking but I'll give it a shot. Intermolecular forces do not change when a substance undergoes a phase change, such as when something goes from a solid to a liquid. The same intermolecular forces that existed when something was a solid still exist when it changes to a liquid, and vice versa. Its just that with the addition of an external factor (most commonly an increase in temperature) a substance is able to overcome the attractive forces in the solid and break apart into a liquid or when a liquid turns into a gas. For when something freezes or condenses the opposite happens, an external factor (most commonly a decrease in temperature) causes a given substance to be attracted to itself more strongly and then the substances comes together as either a liquid or a solid. In summary: The forces do not change. Just how much the forces effect the overall substance changes.
Why does the temperature of melting ice stop rising when it begins to turn into water?
It's because the molecules' intermolecular forces must break in order to become a liquid, and inorder to break those attractions, you must apply energy into the substance. When there are no more intermolecular forces to break, then the kinetic energy/temperature will increase again.
What is wrong with this statement, "As a substance freezes, it absorbs energy equal to its enthalpy of fusion"?
There is nothing inherently wrong with the statement "As a substance freezes, it absorbs energy equal to its enthalpy of fusion." In fact, this statement is a well-established scientific principle known as the Enthalpy of Fusion. When a substance changes from a liquid phase to a solid phase (freezing), it undergoes a phase change that requires a specific amount of energy to overcome the intermolecular forces holding the substance together. This energy absorbed is known as the Enthalpy of Fusion, and it is dependent on the substance and specific conditions. Therefore, this statement accurately describes the process of freezing and provides important information about how substances behave during phase changes.
The phase of matter depends on what?
Heat and pressure are the two main factors that determine a substance's current phase.With high heat a substance's phase drifts toward the gaseous phase while freezing temperatures cause it to move toward its solid phase. With pressure it is the opposite. Higher pressures push the substance toward its solid phase, while lower pressures will encourage the substance to evaporate into its gaseous phase.
Properties that affects the melting and boiling points of a molecule?
The melting point and boiling point of a substance come under the category of phase changes. And the temperature at which these phase changes occur are related to the intermolecular forces holding the molecules of the substance together.
What variables that responsible of the three phases of matter?
Three factors affected during a phase change would be temperature, pressure and intermolecular forces/internal energy.
What is the difference between surface tension and interfacial tension?
interfacial tensions are similar to surface tensions in which cohesive forces are also involved but the major forces are adhesive forces (tension) between liquid phase of one substance and either solid liquid or gas phase of another substance and interaction occurs at their surfaces
What is the phase with the highest kinetic energy and lowest intermolecular attractions?
the gas phase
What is the intermolecular forces for lithium fluoride?
Lithium chloride is a very hygroscopic ionic chloride sat. It is NOT molecular in the solid or in solution. It is a diatomic molecule in the gas phase and has a high dipole moment due to the difference in electronegativity between Li and Cl, intermolecular forces in the gas phase will be dipole -dipole and dispersion forces.
