i fill two ice trays, one covered and one not. The ice in the covered tray freezes the ice to the point that the ice is much more difficult to extract from the tray. Why is that?
Bit of an odd one here, perhaps, but I'm hoping to get some back-of-the-envelope concept of how quickly a water channel that was melted into a block of -170 degree water ice would re-freeze. It's similar to trying to determine what would happen if I went ice-fishing on a comet in deep space --...
I don't know what the weather has been around the nation and world this week, but here in the great NW we have been freezing our buns off! All week we [at our house] were at or below 10 degrees F at night, with daytime highs well below freezing. Today we finally hit 33 degrees with freezing rain...
Homework Statement
Hi, I have a problem with the data and calculations part in my lab. For some reason, I can't get a molar mass of the given solutes to match my answer. I'll provide all the equations and my numbers. Please I really need help with this
Homework Equations
deltaT = m(kf)...
Homework Statement
Find the molar mass of a nonpolar molecular compound if 5.52 grams dissolved in 36.0 grams of benzene begins to freeze at -1.87 C? The freezing point of pure benzene is 5.50 C. The freezing point depression constant is -5.12.
Homework Equations
(Change of...
A quick google search reveals conflicting opinions on whether or not this will have a negative impact on battery life. I carry my laptop outdoors with me every day on my walk from the train to the hospital, do I need to worry about the cold ruining my battery?
Homework Statement
The enthalpy of fusion of mercury is 2.292 kJ/mol, and its normal freezing point is 234.3 K with a change in molar volume of +0.517 cm/mol on melting. At what temperature will the bottom of a column of mercury (density 13.6 g /cm3) of height 10.0 m be expected to freeze...
I love this thing. I don't know how many of you have seen this before, but it is absolutely amazing. Took me quite some time to get it going for so long. Usually, it only went for about 2 minutes and then fell over. Then I had this brainwave to keep it in the freezer for a while. When I took it...
It is very hard to have homogeneous nucleation in common situation. Pure water with no nuclei at all will not freeze above -40oC. The presence of impurity particles allow the so-called heterogeneous nucleation to occur so that we can see water freeze at 0oC. It may be reasonable to guess at what...
Homework Statement
You have a 10.4g mixture of sugar (C12H22O11) and table salt (NaCl). When this mixture is dissolved in 150g of water the freezing point is found to be –2.24 degrees centigrade. Calculate the percent by mass of sugar in the original mixture.
Homework Equations
delta...
1. Homework Statement [/b]
question 1: Calculate the mole fraction of benzene in benzene-toluene solution that is in equilibrium at 25 deg. Celsius with a vapor pressure that contains 62% mol Benzene. At 25 deg. Celsisus the vapor pressures of benzene and toluene are 95.1 mm Hg and 28.4 mm Hg...
Homework Statement
Water in rock crevices often causes erosion when it freezes, given it expands and exerts pressure on the rock. What is the maximum pressure that water can exert when it freezes?
T = 263.15 K
dice @ 263.15 K = 0.9 g cm3
dwater @ 263.15 K = 1.0 g cm3
Homework Equations...
Hi all,
I have a heat transfer problem. In this problem, a water drop (assume sphere) is falling from a very high building. The outside temperature is below zero say -20 degree centigrade. How much time will it take to freeze?
I am not able to understand how to model this problem. Which...
Homework Statement
A 100 g mass of supercooled water at -2ºC in thermal contact with surroundings also at -2ºC
freezes spontaneously.
Calculate the entropy change of the universe assuming that the surroundings act as a large
temperature reservoir. [The specific heat capacity of ice is 2090 J...
So we need a new picture and the weather is freezing fog. Hence rime ice time. The bigger waters are still open, the fog is more intense there, the place to go for new rime ice pictures.
100% crop
100% crop
Now, which one to enter in the contest?
freezing Beer in the Heat!
Hey everybody!...
the other day i had a few Beers in the refrigirator...i went to get one and i grab one...it was liquid...it wasnt frozen as the others...then when i open it up...it started to frozen from top to botton continuosly!...it took like 15 seconds to do...
Why is the vapour pressure lowered when non volatile solute is added to a solvent?
What is the physical reason?
Also, why do binary solutions freeze over a range of temperatures, not at one specific temperature?
Thanks guys, as usual, for sharing the knowledge!:smile:
Homework Statement
No data
Homework Equations
No equations. Theory
The Attempt at a Solution
Freezing the soda can will makes the soda can contract, thus increasing the pressure of the soda. P=F/a.
However, as pressure had increase, to the air particles in the soda can will have...
1.
The diagram shows a strip of paper tape that has been pulled under a vibrating arm by an object moving at constant speed. The arm is vibrating regularly, making 50 dots per second.
What was the speed of the object?
A. 2.0cm/s B. 5.0cm/s C. 100cm/s D. 200cm/s
Completely clueless...
Homework Statement
One mole of two different compounds happens to weight the same, but one compound ionizes in water and the other does not. Which will give the lowest freezing point depression?
Homework Equations
The Attempt at a Solution
Homework Statement
1.Antifreeze used in your car is ethylene glycol, HO-CH2-CH2-OH. It is usually diluted 1:1. Assume that you made a solution of 50 g of water (solvent) and 50 g of ethylene glycol (solute). What temperature in Celsius would your car be protected to in cold weather? Assume...
If you did had a container that was strong enough to resist the expansive forces generated as the water in it freezes, what would happen? (assuming the container is filled completely with water)
Thanks for any answers in advance, and I hope this post is in the correct place, if not, then sorry!
Hey
I have to do some spectroscopy of whole blood. But I can only get freezed blood. Is freezed blood different from 20 degree blood. Any chemical differences? does freezing destroy elements of blood.
regards
MB
Hello,
Iv'e freezed a bottle of water, which was feeled up to the top, with no room for air. After I took it out of the freezer I of course licked the ice, and it taseted like salt (not very pleasent)!
Is it salt?
If you freeze ice in a bottle which does have some space for air this doesn't...
Have they identified the genes behind frogs being able to produce antifreeze and surviving freezing themselves that way? Can anyone shed more light on frogs freezing themselves? thanks
check it out:
or this one:
& this CBC report:
http://www.cbc.ca/clips/mov/jones-cold080129.mov
:bugeye: Luckily for people who don't like the cold it will warm up a bit by the weekend. I like it the way it is though. :approve:
i was just wondering why salt, when it dissociates into Na an Cl as it is dissolved into water, decreases the freezing point of water. Why does more energy have to be taken out of the system? does it have to do with entropy or what?
i found this in a textbook.
at a high altitude the temperature of the atmosphere is 500 degrees centigrade. yet an animal there would freeze to death and not boil. why does this happen?
Homework Statement
Calculate the freezing point and boiling point of each of the following solutions using the observed van't Hoff factors in Table 11.6.
(a) 0.070 m MgCl2
Temp Freezing?
Temp Boiling?
(b) 0.020 m FeCl3
Temp Freezing?
Temp Boiling?
Homework Equations...
Homework Statement
Ethylene glycol, the primary ingredient in antifreeze, has the chemical formula C_2H_6O_2. The radiator fluid used in most cars is a half-and-half mixture of water and antifreeze.
What is the freezing point of radiator fluid that is 50% antifreeze by mass? K_f for water...
Is it possible for water on the surface of a road to freeze even though the temperature of the air just above the road is above 0 degree Celcius?
I think the answer is yes but i do not have any theories to support it.
It may be because the air above is is above 0 degrees so it tends to rise...
http://www.collegehumor.com/video:1755006
This may be old but...
How does this work? They need to have a huge warmth transfer coefficient for this to happen? Maybe the water is at 0°C already and a small amount of energy should be taken to get this effect. Is it electromagnetical or is the...
My girlfriend's computer is incessantly freezing, or when it does function it will freeze the minute you go idle for about 20 minutes. It's irking her and I was wondering what the cause of this is and how to fix it?
She has a Windows XP operating system.
I have a Gallon of water at room temperature at Sea Level.
I want that gallon completely frozen in 5 seconds.
Supposing you don't account for impurities (ie. it's pure water)...
1) Is this possible?
2) How cold would it have to be?
Let's say you add 50% salt...
1) Is this...
Assume that the density of water is 1.00 g/ml . Calculate the quantity of KBr that would need to be added to lower the freezing point of 535 ml of water by 1.40 degree celsius:
What I'm trying to do is the following:
Step 1:
Tf = Kf . m
I took Tf = 1.4
Kf = 1.86
and found the...
Hi Guys,
I have a question and its regarding to the freezing point depression lab ... I did an experiment where I had to find an "i" value for KCl. I'm getting 2.4 for "i" ... but the theoratical value is 2.
I was just wondering why expriment value os higher than the theortical value ? what...
So we did an experiment of freezing point depression and my calculated molar mass values were larger than actual...
First, the freezing point of the pure solvent had to be determined and so if some of the solvent was on the walls of the test tube opposed to in the solution how would this affect...
Almost every time I start up my computer, on the POST logo, it shows like colourful lines, when it goes to anything that has text in it such as the BIOS setup or anything like that, I have these weird characters and all this random stuff, such as the DOS text for smiley faces. It also will...
In "Frozen Light" an article written by Lene Vestegaard Hau, it talks about Lene's experiments with, literally, slowing down light by way of passing it through "ultra-cold clouds of atoms." The experiment was undertaken at Cambridge and Lene and a group of researchers were able to get light's...
Heyas.
Recently my brother showed me a trick with a plastic bottle of very cold water. It was out of the freezer, pretty cold, but not frozen. He took the bottle and slammed it against the counter and the bottle froze up. I'm at a loss for explaining why this happens.. The only thing I can...
Water – Boiling and Freezing
What started as a question has become my own answer. While waiting the 15 minutes or so for this site to send me my new authorization, I found my answers to…
Many years ago I watched a science show hosted by a professor called Julius Sumner-Miller, who would...
When you make ice cream using a couple of zip loc bags and a salt/ice mixture do the room and surroundings have any effect? Can you be in a warm room and still make the ice cream? Thanks.
First please note that I have never taken a physics class in my life. The only reason that I have any clue whatsoever about what went on is because of SCUBA equipment and paintball markers. I have completed a brief search in the forums here and have not found a sutible answer. We have come...
Hi
Its the holidays and i was just thinking if you have a jar with some water in it and you put it in a freezer say 0 degrees and the jar is constantly being shaken rapidly would the water freeze up over time? or simply if a body of water is moving does the freezing point decrease in...