Higher Melting Point

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Elizabeth Kaplan 3I
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Higher Melting Point

Postby Elizabeth Kaplan 3I » Mon Nov 16, 2020 11:12 pm

Why does CHI3 have a higher melting point than CHF3?

Melis Kasaba 2B
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Re: Higher Melting Point

Postby Melis Kasaba 2B » Tue Nov 17, 2020 12:11 am

CHI3 has a higher melting point than CHF3 because it's a bigger atom. Being larger means that CHI3 has more electrons, and thus a higher polarizability (more easily distortable cloud of electrons), which creates a stronger intermolecular bond, making it harder to melt.

Anh Trinh 1J
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Re: Higher Melting Point

Postby Anh Trinh 1J » Tue Nov 17, 2020 1:52 am

I has more electrons than F, because Iodine is in a higher energy level than Fluorine, and since the trend for polarizability is increasing down the periodic table, Iodine is more polarizable. Also, as the size increases, the boiling point also increases (and vice versa), so CHI3 has a higher melting point.

Jessica Katz
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Re: Higher Melting Point

Postby Jessica Katz » Tue Nov 17, 2020 11:04 am

It has a higher melting point because iodine has a much higher amount of electrons than fluorine, so it will occupy a larger volume and create a larger surface area. The larger surface area creates a stronger force between two CHI3 molecules versus two CHF3 molecules. The increase in atomic size and surface area causes an increase in melting point.

Inderpal Singh 2L
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Re: Higher Melting Point

Postby Inderpal Singh 2L » Tue Nov 17, 2020 3:37 pm

CHI3 has a higher melting point because it is bigger.

Isabel_Eslabon_2G
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Re: Higher Melting Point

Postby Isabel_Eslabon_2G » Tue Nov 17, 2020 3:49 pm

Comparing melting points involves looking at intermolecular attraction. To solve this you need to compare the London dispersion forces of CHI3 and CHF3. When comparing dispersion forces, CHI3's is stronger than CHF3's because the iodine in CHI3 has more electrons than the fluorine in CHF3. For dispersion forces, more electrons means that the forces are stronger and require more energy to separate multiple CHI3 molecules vs. multiple CHF3 molecules. Since CHI3 needs more energy, it has a higher melting point.

Ariel Guan 1H
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Re: Higher Melting Point

Postby Ariel Guan 1H » Thu Nov 19, 2020 5:15 pm

CHI3 is larger than CHF3 (I is bigger than F), so the forces in CHI3 are stronger, which means that you need more energy for it to melt.

Alen Huang 2G
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Re: Higher Melting Point

Postby Alen Huang 2G » Fri Nov 20, 2020 2:11 pm

CHI3 has more electrons thus higher dispersion forces so its intermolecular forces are stronger than the intermolecular forces in CHF3 since both molecules have dipoles the only difference in their intermolecular forces is the strength of the dispersion forces. Stronger forces mean more energy is required to break them apart and thus higher melting point.

Marco Vivar 3G
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Re: Higher Melting Point

Postby Marco Vivar 3G » Sun Nov 22, 2020 8:49 pm

Its bigger thus more space for LDF to affect the atom

Alison Perkins 2B
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Re: Higher Melting Point

Postby Alison Perkins 2B » Sun Nov 22, 2020 8:51 pm

It has a higher melting point because it has more electrons, making it a larger molecule with more electronegative forces acting upon it, making it more difficult to break the bonds.

Danielle DIS2L
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Re: Higher Melting Point

Postby Danielle DIS2L » Sun Nov 22, 2020 10:00 pm

CHI3 has a higher melting point than CHF3 because I is a bigger atom than F meaning that I is more polarizable(more easily distortable cloud of electrons) indicating that there is a stronger intermolecular bond.

kristinalaudis3e
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Re: Higher Melting Point

Postby kristinalaudis3e » Sun Nov 22, 2020 11:59 pm

CHI3 has a higher melting point because it has stronger bonds. Because of its size, it has more polarizability.

Violet Kwan 3H
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Re: Higher Melting Point

Postby Violet Kwan 3H » Mon Nov 23, 2020 12:03 am

It has a higher melting point because the Cl atoms are larger with more energy levels. This means that it is more polarizable and therefore has stronger LDF interactions.

Geethika Janga 1L
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Re: Higher Melting Point

Postby Geethika Janga 1L » Mon Nov 23, 2020 12:04 am

CHI3 has a higher melting point than CHF3 because it has more electrons, making it the bigger atom. Since CHI3 is larger, that also means that it will have a higher polarizability. This means that the cloud of electrons surrounding the nucleus will be more easily distorted and can create stronger intermolecular bonds with the surrounding atoms. Since melting requires breaking bonds, the molecule with a greater number/stronger bonds will be harder to melt.

Gabriel Nitro 1E
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Re: Higher Melting Point

Postby Gabriel Nitro 1E » Mon Nov 23, 2020 9:19 am

Hi,

This is because the atomic radius of the iodine atom is far larger than that of the fluorine atom. This leads to increased polarizability, increased LDFs, and increased strength of intermolecular attractions.

The more energy required to disrupt these interactions, the higher the temperature needed to induce the same effect of melting, and thus the higher the melting point.

Hope this helps! :)

simona_krasnegor_1C
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Re: Higher Melting Point

Postby simona_krasnegor_1C » Sat Nov 28, 2020 2:37 pm

Iodine's larger amount of electrons make it a bigger atom. This big size creates a high polarizability, making it harder to melt and therefore have a higher melting point.

Simi Kapila_3E
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Re: Higher Melting Point

Postby Simi Kapila_3E » Sat Nov 28, 2020 3:05 pm

CHI3 has a higher melting point because it is bigger, and thus more polarizable. Additionally, when atoms are bigger, they have stronger london dispersion forces. since I is bigger than F, CHI3 has stronger london dispersion forces than CHF3, and thus is harder to dissociate and harder to melt.

Muskaan Abdul-Sattar
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Re: Higher Melting Point

Postby Muskaan Abdul-Sattar » Sun Nov 29, 2020 10:04 pm

Because CHl3 is larger, it has stronger forces that make it harder to melt.

Madeline Ogden 3B
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Re: Higher Melting Point

Postby Madeline Ogden 3B » Tue Dec 01, 2020 12:45 pm

Iodine is a larger atom with more electrons than fluorine. Because of this, it has stronger bonds. This not only explains why CHI3 has a higher melting point than CHF3 but also why F2 is a gas at room temperature while I2 is a solid.

Mary Gallo 1G
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Re: Higher Melting Point

Postby Mary Gallo 1G » Tue Dec 01, 2020 1:23 pm

CHI3 is larger than CHF3 and therefore has stronger London Dispersion forces. There is more energy required to dissociate the atoms in CHI3 so its melting point is higher.

Aria Movassaghi 1A
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Re: Higher Melting Point

Postby Aria Movassaghi 1A » Sun Dec 06, 2020 10:30 pm

Due to increased atomic radius, bigger atom means higher boiling point.

Ke Huang 2G
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Re: Higher Melting Point

Postby Ke Huang 2G » Sun Dec 06, 2020 10:38 pm

CHI3 has a higher melting point because I has more electrons, which creates more polarizability.

Susan Chamling 1F
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Re: Higher Melting Point

Postby Susan Chamling 1F » Sun Dec 06, 2020 11:11 pm

CHI3 has the higher melting point because Iodine is a larger atom than Fluorine, which has the smaller atomic radius. Since it is larger, Iodine has higher LDFs and polarizability, and since more energy to break interactions means a higher temperature, CHI3 will have the higher melting point.

arisawaters2D
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Re: Higher Melting Point

Postby arisawaters2D » Thu Dec 10, 2020 12:27 pm

Why do larger molecules have higher boiling points? I thought a larger molecule meant a weaker bond.

Jason Knight - 1F
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Re: Higher Melting Point

Postby Jason Knight - 1F » Thu Dec 10, 2020 1:45 pm

CHI3 has a higher melting point than CHF3 due to the larger atomic size and surface area of Iodine. Iodine has the greater amount of electrons, hence a larger surface area than Fluorine.

Chris_Butler_1A
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Re: Higher Melting Point

Postby Chris_Butler_1A » Sat Dec 12, 2020 5:16 pm

I had a little confusion here as well. I would have thought that due to Fluorine having a higher electronegativity than Iodine that surely it would have a higher melting point. However, it seems that melting and boiling point depends on the bonds and intermolecular forces within the atom. Given Iodine's larger size when compared to Fluorine, there exists more surface area in which Iodine could bond, causing it to have a higher melting point in this case.

LovepreetSran_3H
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Re: Higher Melting Point

Postby LovepreetSran_3H » Sat Dec 12, 2020 5:19 pm

CHI3 has a higher melting point because iodine has a larger atomic radius meaning that it has more electrons.

Joshua Chung 2D
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Re: Higher Melting Point

Postby Joshua Chung 2D » Sun Dec 13, 2020 1:16 pm

Since Iodine is a larger molecule than Fluorine, the bond is stronger due to it being easier to distort its electrons. Thus, the compound with iodine is harder to break, resulting in a higher melting point.


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