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How do you determine melting point of a compound that sublimes or decomposes before melting?
Wiki User
∙ 14y ago
You don't. You determine the sublimation point or the decomposition temperature instead. In a table of melting points, such a compound would have a temperature listed along with a notation along the lines of "subl" or "dec".
Wiki User
∙ 14y ago
Wiki User
∙ 15y agoit has sublimed (changed from a solid to a gas) the glass tube needs to be sealed (with heat) before the mp can be determined
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What steps can you take to determine the melting point of a substance that sublimes before it melts?
In such cases the melting point determination must be performed in a sealed capillary tube to avoid loss of sample. This can be achieved by heating the open end of the capillary tube, and with tweezers forcing it shut.
Is a solid with a melting point of 800 degrees Celsius ionic or molecular?
The melting point of a compound cannot determine the bonding structure. As an example, both diamond and sodium chloride have higher melting points than 800 centigrade but are covalent and ionic compounds respectively.
What happens when a solid sublimes?
When ice sublimes, the molecules at the edge of the ice escape into the gas phase as water vapor. The solid phase thus turns directly into the gas phase without an intermediary liquid phase. Ice sublimes quite slowly under normal conditions, but dry ice (solid carbon dioxide) sublimes readily at everyday temperatures and pressures.
What is the boiling point of iodine in kelvin degrees?
457.4 K. note iodine sublimes uunder normal conditions i.e. vaporises without melting
What are the applications of finding the melting point of an organic compound?
To check the purity of the organic compound.
What steps can you take to determine the melting point of a substance that sublimes before it melts?
In such cases the melting point determination must be performed in a sealed capillary tube to avoid loss of sample. This can be achieved by heating the open end of the capillary tube, and with tweezers forcing it shut.
Is a solid with a melting point of 800 degrees Celsius ionic or molecular?
The melting point of a compound cannot determine the bonding structure. As an example, both diamond and sodium chloride have higher melting points than 800 centigrade but are covalent and ionic compounds respectively.
How do you determine the type of compound ionic or molecular from the melting point such as 1240 degrees C?
If the melting point is at 1240 degrees C then it is most likely an ionic compound, because ionic compounds have their melting points above 800 degrees C while the molecular compounds have their melting point at or below room temperature.
For what two reasons are the melting points routinely used?
1- determine the purity of a substance 2- determines the characteristic of the compound
How do you determine the melting point of dibenzylideneacetone?
Get melting point apparatus; determine.
Is bicarbonate a solid?
Yes, it is solid at room temperature and has a melting point of 270oC (decomposes).
What happens when a solid sublimes?
When ice sublimes, the molecules at the edge of the ice escape into the gas phase as water vapor. The solid phase thus turns directly into the gas phase without an intermediary liquid phase. Ice sublimes quite slowly under normal conditions, but dry ice (solid carbon dioxide) sublimes readily at everyday temperatures and pressures.
Is an alloy of aluminum has a melting range instead of a melting point is the alloy a compound?
It is a compound. All pure elements have a certain exact melting point.
How is the melting of an impure compound expected to change with recrystallization?
The melting point of an impure compound will become closer to that of the actual melting point of the pure substance with recrystallization of your mixture.
Melting point of ice in kelvin?
The diamond has no melting point. The triple point for carbon is about 11 MPa and about 4600 K. Rather than melting, carbon sublimes at about 3900 K.
What is the boiling point of iodine in kelvin degrees?
457.4 K. note iodine sublimes uunder normal conditions i.e. vaporises without melting
Does diamond have the highest melting point?
Diamond do not melt, it sublimes (solid-gas) at 3642 degrees Celsius.
