Melting Definition and 275 Threads

Question: The heat of vaporization of water is 2260 J/g at 100°C. A 100.0 g sample of water condenses and all of the heat liberated is then transferred to a block of ice. How many grams of ice will melt? Assume the condensed water remains at 100°C and the melted ice remains at 0°C. The heat...

Does anyone have or know where I can find literature values for the melting points (or melting ranges) of the following three semicarbazone compounds? 4-Methoxybenzaldehyde semicarbazone Isopropylbenzaldehyde semicarbazone Carvone semicarbazone (either the R or S diasteriomers) I haven't been...

Hi all, i am currently studying for an exam, and so i am going over the questions in last years exam. Unfortunately we were not given the answers, so i am not sure whether i am getting the questions right. If its not too much trouble, and someone has a bit of time to spare, could they verify...

I am wondering about the enthalpies of solids and liquids near the melting temperature. I am familiar with free energy, and I know that above Tm, free energy of the solid becomes higher than liquid. However, we have been asked to think about the same question for enthalpy and draw a schematic. I...

Is it possible to melt a perfect mirror by radiative means? (reflects light of all frequencies with no absorption) Which leads me to ask. What is the mechanism (at the atomic level), for the reflection of light? I've never had a satisfactory answer on the mechanism of reflection. Is it...

If we could determine how much ice is melting in the polar caps we could find out how many powerstations it would take to refreeze the ice.

Just thinking about those stories you hear about dresden and tokyo. The ones about people being melted alive in bunkers. Exactly what conditions would have to exist for that to be possible?

Hi.. I've finished this topic but I was confused in this question. The question is : The main reason for the high melting point of water compared to other group4 hydrides can be explained by: a.Ionic Bonding b.Covalent Bonding c.Dispersion Forces d.Hydrogen Bonding I'm not sure...

Any of u heard of him? the founder of Hutchison effect, I am very interested in his work but i really don't know how he did those werid things espcailly the melting of metals at room temperature, would someone care to explain a little about his effect? (or has any of you never heard of him?)

Global warming and "glaciers melting" In another thread I promised to go over all the alarming climate features like glaciers melting, sea levels rising etc, I think that was actually off topic over there so I start a fresh one. About the glaciers and ice sheets; yes, most glaciers are...

Hi, does anybody know why the melting points of materials drop down when its size gets smaller down to nano-scale? For a nano particle set in another high-melting-point material, how does its Tm go?

hey all, i'd just like to say thanks for attempting to help or just even having a browse. i have 5 questions in which i have some idea about but still very hard to produce an answer. 1: What is the difference in boiling point of water between sea level (p = 1 atm) and on top of a mountain...

What law or physics principle is that? Thanks for the help.

A person makes a quantity of iced tea by mixing 559 g of hot tea (essentially water) with an equal mass of ice at its melting point. If the initial hot tea is at a temperature of 94 C, what are the (a) final temperature of the ice tea (in oC) and (b) mass of the remaining ice? what are the (c)...

does anyone know why it is important to have the melting point of a solute not be higher than the boiling point of the solvent during recrystallization? --having a little trouble rationalizing this.

I have trouble figuring out the following question. Please help. ------------------------------------------------------------------------ Suppose you want to melt a piece of ice and boil the resulting water by using a microwave oven. The radiation is incident upon one side of the ice which...

what is the relationship between e-modulus and melting temp?

I have a sample of 25 % acetanilide with 75 % caffeine. I record a melting point range of 198 - 240 degrees celcius acetanilide's melting point is 114.3 caffeine's melting point is 238 What would cause this huge experimental range? My thinking is that the acetanilide is...

Boiling/ Melting... I take it everyone knows the graph of temperature when you heat ice / water - with the flat bits when it melts and boils. My question is why is this the case? Obviously the heat energy you are putting in is going to kinetic energy of the particles when the graph is not flat...

Problem 2. Liquid nitrogen, which has a boiling point of 77 K, is commonly used to cool substances to low temperatures. How much energy must be removed from 1.4 kg of gaseous nitrogen at 77 K for it to completely liquefy? Assume the latent heat of liquid nitrogen is 2.01 *10^5 J/kg Answer...

[Originally posted to material science forum but no reply] It's no surprise that if I take a particular metal and 'add' atoms of a second metal that has a lower melting point that the Tmelt of the combination is usually lower than that of the pure metal. This is hypoeutectic composition...

It's no surprise that if I take a particular metal and 'add' atoms of a second metal that has a lower melting point that the Tmelt of the combination is usually lower than that of the pure metal. But it seems surprising that if a reverse this, take a low Tmelt metal and add atoms of a higher...

Ok, so you've got a glass of water with some ice (the ice is floating). After the ice melts, does the water's surface level a) rise? b) lower? c) stay the same? (and why?)

stuck in explaining this problem A glass of water contains a large ice cube the glass can hold no morw water the ice is floating in the water what will happen to the water level when the ice melts?

Who can calculate the meltingpoint for me of a mixture of metals with 40% Sn and 60% Pb?