Part A: What happens to temperature as naphthalene melts?
Objective: As heat is applied to liquid naphthalene, the temperature rises. As the temperature rises, the naphthalene will eventually start to melt. This lab experiment tries to answer the question: what happens to the temperature of naphthalene as it melts? In this lab, you will heat the liquid naphthalene, and record the temperature changes. You will graph the temperature changes before drawing any conclusions.
Part B: Determining the freezing point of naphthaleneObjective: Freezing point is a characteristic property of matter. As heat is taken away from a liquid, the temperature of that liquid decreases as the substance begins to freeze. This lab experiment tries to answer the question: what is the freezing point of an unknown liquid (naphthalene)? In this lab, you will cool liquid naphthalene, and record the temperature changes. You will graph the temperature changes before drawing any conclusions.I do not have data on rate of sublimation, but it is safe to say that naphthalene sublimes faster with increasing temperature. At some low temperature the sublimation rate will approach 0. It melts at 176 deg F. At this temperature sublimation, which by definition involves a solid going to a gas can not happen. You can safely assume it will gas off even more as a liquid. It boils at 424deg F.
During the phase change of a solid to a liquid (melting), all of the energy goes into breaking the intermolecular bonds holding the molecules of the solid together, and none of the energy goes into changing the temperature. Thus, during this particular phase of melting, the temperature of the system does NOT change.
i dont know at all
because of phase transtion i.e. from solid to liquid during melting and from liquid to vapour during boiling. so just to change over from one phase to the other heat is totally utilized.
It is possible to add heat to a substance without changing its temperature. That happens during melting and boiling. However, I cannot think of a case in which the temperature of a substance increases without heat being added to it, either by radiation, conduction or convection.
The temperature remain constant during the phase changing.
During melting the temperature remain constant if it was achieved the melting point.
Temperature of melting iceis a constant property: it does not change during melting (stays 0oC, this is even one of the the defined value of the Celsius temperature scale)(for any other melting solid the same is valid at each melting point temperature)
to ensure that the temperature is uniform throughout the liquid
Naphthalene, which is found in mothballs, when heated sublimes (which means it changes from a solid directly into a gaseous state without going through the liquid state).
you must have observed during the experiment of melting that the temperature of the system does not change after the melting point is reached till all the ice melts this happens even though we continue to heat the breaker that is we continue to supply heat
The intermolecular forces of attraction in the solid decreases as it is heated and the solid melts (solid converts to liquid) at its melting point.
No. The temperature does not change during the melting process. All of the heat energy is used to break the bonds of the solid to form a liquid, i.e. the energy is used in the phase change, and thus is not used to raise the temperature.
Melting and evaporating are both a change in matter.also during evaporation and melting there is no change in temperature
melting and evaporating are both a change in matter. also during evaporation and melting there is no change in temperature. melting and evaporating are both a change in matter. also during evaporation and melting there is no change in temperature.
yes it is. Its melting so its becoming a liquid
During the phase change of a solid to a liquid (melting), all of the energy goes into breaking the intermolecular bonds holding the molecules of the solid together, and none of the energy goes into changing the temperature. Thus, during this particular phase of melting, the temperature of the system does NOT change.
A change in temperature occurs during both freezing and melting. Freezing and melting are physical changes since the chemical contents of the matter do not change.