Physics Van 3-site Navigational Menu

Physics Van Navigational Menu

Q & A: Lowering of Melting Point

Learn more physics!

Most recent answer: 07/24/2016
Q:
Why does salt stop water from freezing?
cheater click wifes who cheat
married woman looking to cheat go most women cheat
married woman looking to cheat go most women cheat
buy sildenafil 100mg viagra without a doctor prescription viagra 100 mg
discount card prescription damske.com print cvs
levitra pill go tadalafil pill
finasteride sigridw.com cialis 80mg
prescriptions coupons go discount coupon for viagra
prescription drugs coupons viagra manufacturer coupon 2016 viagra coupon card
can i take minocycline with birth control read can i take minocycline with birth control
cialis dosage and cialis dose for copd pts
diabetes affect sexuality open diabetes sexuality treatment
acheter viagra pas acheter viagra pas acheter viagra pas
viagra bestellen online viagra online shop pillen kopen
cialis manufacturer coupon link prescription drug coupons
lilly cialis coupon coupons for prescriptions coupons prescriptions
naproxennatrium site naproxen migraine
kamagra wikipedia blog.jrmissworld.com kamagra shop
motilium enceinte site motilium et grossesse

- Rachel (age 14)
Kincumber, NSW, Australia
A:

Looking over our old answer (below), I realized that we said many interesting things but did not actually answer the question "why". Maybe whoever wrote the first draft didn't know the answer, and we just patched it to remove errors.  Anyway, here's why.

Say you have a cup of pure water and a cup of somewhat salty water. As you lower the temperature some of the pure water starts to form ice crystals. The reason is that although the frozen water molecules, lined up into a crystal,  have fewer ways to move around (lower "entropy") than the liquid molecules, they release heat when they freeze and that raises the entropy of the surroundings even more. So the net entropy goes up as the water freezes, as it always does on the way to any equilibrium state.

What about in the salty water? There's one extra term in the entropy change. The salt doesn't fit into the ice crystals. So as they form, the remaining salt is left with less room to roam around in, and thus less entropy. So you have to get the salt water even colder before you get a net entropy gain from freezing it.

It sounds like that explanation isn't special to salt- it should work for any molecules or ions dissolved in the water. And so it does.

Now for the old discussion:

If you live in a place that has lots of snow and ice in the winter, then you have probably seen the highway department spreading salt on the road to melt the ice. You may have also used salt on ice when making home-made ice cream. Salt lowers the freezing/melting point of water, so in both cases the idea is to take advantage of the lower melting point.

Ice forms when the temperature of water reaches 32 degrees Fahrenheit (0 degrees Celsius). When you add salt, that temperature drops: A 10-percent salt solution freezes at 20 °F (-6 °C), and a 20-percent solution freezes at 2 °F (-16 °C). On a roadway, this means that if you sprinkle salt on the ice, you can melt it. One way you can think about this is that the salt is so dry, so hungry for liquid water, that it actually pulls liquid water out of the ice. You can see that salt is hungrier for water than a drop of pure water would be, because salt certainly gets wet and dissolves when it's put near water. That's shows it's better at attracting liquid water than water itself is, and so it can pull water out of ice at a lower temperature than pure water can.

If you ever watch salt melting ice, you can see the dissolving process happen -- the ice immediately around the grain of salt melts, and the melting spreads out from that point. Those melted spots are actually very salty. Once the salt crystals are used up, they start to get diluted, more like ordinary liquid water, and their freezing point goes back up. If the temperature of the roadway is lower than 15 °F or so, then the salt can only melt a small amount of the ice. (If it gets below about 0 °F, it can't melt ANY of the ice.) In that case, spreading sand over the top of the ice to provide traction is a better option.

When you are making ice cream, the temperature around the ice cream mixture needs to be lower than 32 °F if you want the mixture to freeze. If you tried using pure ice around the bucket, it would warm up to 32 °F before it started to melt. It wouldn't absorb much heat in the process, so you wouldn't get ice cream. If there's a lot of salt around, the ice will melt at around 0 °F, which is cold enough. As the ice melts, it pulls a lot of heat from its surroundings, enough to cool down the ice cream. That's a key point- just warming up the ice or warming up the liquid doesn't soak up a whole lot of heat. Providing the energy to break molecules away from the ice into the liquid does soak up a lot of heat. So you want that melting process to occur cold enough to freeze the ice cream, not up at a temperature where the ice cream is still liquid.

By the way, you may wonder why you have to get the ice cream colder than 32 °F to freeze it. Just like salt water, it has molecules dissolved in the water (sugar,salts, proteins, ...) that lower its freezing point below that of pure water.

hillcrest abortion clinic stories of abortion live abortion video
hillcrest abortion clinic site live abortion video
hillcrest abortion clinic site live abortion video
discount card prescription site print cvs
finasteride sigridw.com cialis 80mg
imitrex 50mg thepoliticalsword.com flagyl 200mg
free viagra samples coupon gallaghermalpractice.com viagra 2016 coupon
new prescription coupon viagra coupons printable prescription coupon card
coupons for prescriptions floridafriendlyplants.com prescription drugs discount cards
viagra coupons free read drug coupons
prescription drug coupons codesamples.in drug coupon
drug discount coupons link discount coupons for prescriptions
claritinekombo warpedfish.co.uk claritine za psa
voltaren ára house.raupes.net voltaren
venlafaxine gewichtstoename idippedut.dk venlafaxine fk
augmentin générique arbot.cz augmentin sirop
naprosyn roche rileytech.net naprosyn nedir
niacine movidafm.net niacin v hrani
sildenafil pfizer link sildenafil sandoz
proscar vs propecia for hair loss proscar proscar pris
fluvoxamine (luvox) blog.tgworkshop.net fluvoxamina bula
cialis driverblog.suddath.com cialis walgreen coupon
allods online cwblog.centralworld.co.th allo allo

(published on 10/22/2007)

Follow-Up #1: freezing saltwater

Q:
If salt lowers the freezing point of water, does that mean that salt water will only freeze at colder temps than pure water?
why people cheat marriage affairs how many people cheat
married men cheat with men women that cheat with married men wifes cheat
cialis dosage and cialis dose for copd pts
diabetes affect sexuality open diabetes sexuality treatment
cialis coupons from lilly prescription drug cards coupons for prescriptions
cialis manufacturer coupon link prescription drug coupons
cialis coupon lilly blog.nvcoin.com transfer prescription coupon
voltaren ára go voltaren
venlafaxine gewichtstoename read venlafaxine fk
venlafaxine gewichtstoename read venlafaxine fk
augmentin générique read augmentin sirop
diflucan 150 diflucan djelovanje diflucan sirup
flibanserin online lasertech.com flibanserin buy
cefdinir red stool ski-club-auringen.de cefdinir nedir
cefdinir red stool cefdinir nedir cefdinir nedir
lasix injetavel lasix efeitos colaterais lasix
cialis coupon card evans.com.mx cialis coupon

- Elliot Frie (age 12)
Stevens Point, Wisconsin, U.S.A
A:
Yes, exactly.

Mike W.
Lee H
why people cheat marriage affairs how many people cheat
cheater click wifes who cheat
internet drug coupons site prescription coupon
married men cheat with men open wifes cheat
types of abortions the weeks of pregnancy what happens when you get an abortion
abortion pill clinics abortion pill prices for abortions
married cheaters redsoctober.com dating for married men
coupons rx prostudiousa.com www.januvia.com coupons
levaquin pill diprolene 0.05% furosemide pill
imitrex 50mg thepoliticalsword.com flagyl 200mg
prescriptions coupons go discount coupon for viagra
prescription drugs coupons go viagra coupon card
pfizer coupons for viagra prescription coupon viagra discounts coupons
manufacturer coupons for prescription drugs viagra coupons 2016 coupon prescription
cialis price online lipseysguns.com cialis price history
cialis coupons from lilly coupon for free cialis coupons for prescriptions
cialis coupon card read cialis coupons from manufacturer
drug discount coupons link discount coupons for prescriptions
augmentin générique arbot.cz augmentin sirop
fluvoxamine (luvox) open fluvoxamina bula
amlodipine 5 mg amlodipine bijwerkingen amlodipine accord
allods online cwblog.centralworld.co.th allo allo
motilium enceinte blog.cr-inside.org motilium et grossesse
how expensive is an abortion abortion clinic abortion clinics dallas tx

(published on 10/22/2007)

Follow-Up #2: Ice can be colder than 0 degrees Celsius

Q:
given it is so cold at north and south pole, is the ice there colder than0 degrees celcius?
hillcrest abortion clinic abortive live abortion video
internet drug coupons site prescription coupon
abortion pill clinics abortion pill prices for abortions
buy sildenafil 100mg viagra without a doctor prescription viagra 100 mg
priligy 30mg go cialis 40mg
online discount pharmacy dotnetblogengine.net coupon for prescription
viagra coupons from manufacturer liberitutti.info drug discount coupons
viagra coupon card free prescription cards discount viagra free coupon
can i take minocycline with birth control can i take minocycline with birth control can i take minocycline with birth control
cialis manufacturer coupon cialis discounts coupons prescription drug coupons
lilly cialis coupon coupons for prescriptions coupons prescriptions
lilly cialis coupon click coupons prescriptions
augmentin générique arbot.cz augmentin sirop
arcoxia 30 arcoxia 90 arcoxia wiki
cialis thepoliticalsword.com cialis walgreen coupon
cefdinir red stool ski-club-auringen.de cefdinir nedir
renovacija stanovanja click renova g
trental cena trenitalia trental nuspojave

- Nicola Carr
A:
Yes it can be considerably colder, just like the ice in your home refrigerator freezer compartment. If the ice is floating in water, like an iceberg in the North Sea or an ice cube in your favorite drink, the ice will probably be very close to the water temperature.  This may be lower than 0 degrees Celsius depending on the salt content.

LeeH
internet drug coupons open prescription coupon
cvs discount card cvs new prescription coupon prescription drugs discount cards
rite aid prescription transfer coupon mesutcakir.com.tr coupon rite aid
diprolene kamagra furosemide 40mg
priligy 30mg bistromc.org cialis 40mg
pfizer coupons for viagra viagra coupon viagra discounts coupons
coupons prescriptions prescription savings cards manufacturer coupons for prescription drugs
lisinopril and bisoprolol lisinopriland.net lisinopril and bisoprolol
diabetes affect sexuality diabetes sexuality treatment
cialis coupons from lilly coupon for free cialis coupons for prescriptions
arcoxia 30 go arcoxia wiki
arcoxia 30 arcoxia 90 arcoxia wiki
niacine movidafm.net niacin v hrani
proscar vs propecia for hair loss proscar proscar pris
cefdinir red stool ski-club-auringen.de cefdinir nedir
renovacija stanovanja renovator renova g
trental cena trental trental nuspojave
vivitrol alcohol vivitrol implant narcan challenge

(published on 10/31/2007)

Follow-Up #3: saltwater freezing

Q:
on follow up question 2 does that mean salt water will freeze slower then normal pure water?
married cheaters site dating for married men
prescriptions coupons go discount coupon for viagra
discount prescriptions coupons pet prescription discount card internet drug coupons
acheter viagra pas acheter viagra pas acheter viagra pas
ibuprofen rapid tracyawheeler.com ibuprofen
seroquel 25 mg read seroquel debljanje
cialis cialis discount cialis walgreen coupon
motilium enceinte motilium notice motilium et grossesse
cialis coupon card evans.com.mx cialis coupon

- Tai
Japan
A:
Salt water certainly starts to freeze at lower temperature than pure water. And it completes freezing at even lower temperature than that. So under normal conditions it will freeze more slowly if the temperature is gradually lowered.

Mike W.
why people cheat infidelity signs how many people cheat
cheater click wifes who cheat
cheater click wifes who cheat
the best android phone link phone tracking apps
married woman looking to cheat go most women cheat
married woman looking to cheat My wife cheated on me most women cheat
married men cheat with men why husbands cheat wifes cheat
ventolin 2mg bistromc.org deltasone 40mg
imitrex 50mg thepoliticalsword.com flagyl 200mg
online discount pharmacy dotnetblogengine.net coupon for prescription
new prescription coupon viagra coupons printable prescription coupon card
pfizer coupons for viagra prescription coupon viagra discounts coupons
coupons prescriptions prescription savings cards manufacturer coupons for prescription drugs
can i take minocycline with birth control can i take minocycline with birth control can i take minocycline with birth control
can i take antabuse and naltrexone can i take antabuse and naltrexone can i take antabuse and naltrexone
diabetes affect sexuality cialis dosage information diabetes sexuality treatment
prescription drug coupons prescription discount coupon drug coupon
claritinekombo warpedfish.co.uk claritine za psa
naproxennatrium site naproxen migraine
champix alkohol mdwguide.com champix
niacine movidafm.net niacin v hrani
kamagra wikipedia blog.jrmissworld.com kamagra shop
ibuprofen rapid tracyawheeler.com ibuprofen
buscopan hund buscopan wirkung buscopan dragees
amlodipine 5 mg link amlodipine accord
vivitrol alcohol what is vivitrol shot narcan challenge

(published on 12/14/2007)

Follow-Up #4: melting point of ice

Q:
what is the melting point of Pure Ice.? I have been asked this and can only think its 0 degrees Celsius !!! What is meant by Pure Ice?....is it because there are no other substances like salt present?
the best android phone link phone tracking apps
internet drug coupons coupons for prescription medications prescription coupon
married woman looking to cheat go most women cheat
married men cheat with men women that cheat with married men wifes cheat
abortion pill clinics abortion pill prices for abortions
priligy 30mg go cialis 40mg
levaquin pill cephalexin 250mg furosemide pill
ventolin 2mg bistromc.org deltasone 40mg
online discount pharmacy dotnetblogengine.net coupon for prescription
prescription drugs coupons viagra manufacturer coupon 2016 viagra coupon card
viagra coupon card blog.brunothalmann.com viagra free coupon
pfizer coupons for viagra prescription coupon viagra discounts coupons
coupons prescriptions blog.brunothalmann.com manufacturer coupons for prescription drugs
coupon for viagra viagra trial coupon viagra discount coupons online
arcoxia 30 go arcoxia wiki
fusidinezuur kopen blog.jp-sa.org fusidic acid
fluvoxamine (luvox) blog.tgworkshop.net fluvoxamina bula
buscopan hund go buscopan dragees
amlodipine 5 mg amlodipine bijwerkingen amlodipine accord
singulair 4 mg granulat scottdangelo.com singulair patient information
prescriptions coupons coupons for prescriptions drug prescription card
trental cena trental trental nuspojave
vivitrol alcohol what is vivitrol shot narcan challenge

- daniel (age 14)
england
A:
You're right on all counts.

Mike W.

.
why people cheat infidelity signs how many people cheat
cheater read wifes who cheat
hillcrest abortion clinic stories of abortion live abortion video
hillcrest abortion clinic stories of abortion live abortion video
types of abortions read what happens when you get an abortion
cvs discount card cvs new prescription coupon prescription drugs discount cards
walgreens coupons deals blog.mrwade.co.uk walgreens photo print coupons
discount card prescription go print cvs
priligy 30mg go cialis 40mg
levitra pill imitrex 25mg tadalafil pill
online discount pharmacy dotnetblogengine.net coupon for prescription
free viagra samples coupon gallaghermalpractice.com viagra 2016 coupon
viagra coupon card free prescription cards discount viagra free coupon
viagra coupon card blog.brunothalmann.com viagra free coupon
prescription discount coupons free prescription drug cards viagra discount coupons online
lisinopril and energy drinks lisinopril and energy drinks lisinopril and energy drinks
acheter viagra pas acheter viagra pas acheter viagra pas
cialis coupon card read cialis coupons from manufacturer
lilly cialis coupon click coupons prescriptions
discount prescription drug cards nationalautocare.com prescription discounts cards
voltaren ára go voltaren
flibanserin online lasertech.com flibanserin buy
sildenafil pfizer link sildenafil sandoz
cialis open cialis walgreen coupon
fluvoxamine (luvox) blog.tgworkshop.net fluvoxamina bula
buscopan hund buscopan wirkung buscopan dragees
cefdinir red stool ski-club-auringen.de cefdinir nedir
allods online cwblog.centralworld.co.th allo allo
motilium enceinte motilium notice motilium et grossesse
cialis coupon card evans.com.mx cialis coupon
prescriptions coupons cialis coupon drug prescription card

(published on 09/07/2008)

Follow-Up #5: entropy and freezing point depression

Q:
Hi, I am a middle school teacher, teaching general science. My students asked me the same question on why salt lowers the melting point of ice. I have read your explanation. However I have some lingering questions:[1] Can you elaborate about the part on "entropy"?[2] I look up "entropy". It seems so complicated as it is under the topic of thermodynamics. Any recommendation on a good website that introduces thermodynamic entropy conceptual. The complex equations are giving me a headache.[3] Is this possible to relate this to the kinetic model of matter?
cheater click wifes who cheat
the best android phone link phone tracking apps
married woman looking to cheat married men that cheat most women cheat
walgreens coupons deals blog.mrwade.co.uk walgreens photo print coupons
free prescription cards go walgreens prints coupon codes
discount card prescription go print cvs
prescriptions coupons discount card for prescription drugs discount coupon for viagra
discount prescriptions coupons mba-institutes.com internet drug coupons
1 wk pregnant abortion pill article on abortion
can i take minocycline with birth control can i take minocycline with birth control can i take minocycline with birth control
lisinopril and energy drinks lisinopril and energy drinks lisinopril and energy drinks
diabetes affect sexuality cialis dosage information diabetes sexuality treatment
cialis manufacturer coupon link prescription drug coupons
lilly cialis coupon click coupons prescriptions
discount prescription drug cards nationalautocare.com prescription discounts cards
claritinekombo warpedfish.co.uk claritine za psa
champix alkohol go champix
fusidinezuur kopen fusidinezuur kopen fusidic acid
niacine movidafm.net niacin v hrani
cialis cialis cialis walgreen coupon
cialis thepoliticalsword.com cialis walgreen coupon
fluvoxamine (luvox) blog.tgworkshop.net fluvoxamina bula
cefdinir red stool ski-club-auringen.de cefdinir nedir
cefdinir red stool cefdinir nedir cefdinir nedir
renovacija stanovanja blog.myexpensesonline.co.uk renova g

- Jerry (age 35)
Singapore
A:

I'm not sure where to find a good website to introduce entropy, but Reif's book in the Berkeley series is very good: . (The Wikipedia entropy article is currently (6/15) hopelessly complex and confusing for somebody first learning the topic.)

The basic idea is this. Take some set of gross fixed conditions, e.g.
{number of molecules, temperature of environment, pressure}. How likely are you to find the molecules in some type of arrangement (liquid, solid)? Nature turns out to be extremely indifferent to which state things are in. In equilibrium the probability of finding something (e.g. liquid) is just proportional to the number of quantum states that look like that. Will the water be liquid or solid? It just depends on which type is consistent with more quantum states. The total number of quantum states that look like the liquid is the product of the number of states of the water that are liquid times the number of states of the environment that go along with the liquid. It's a product for the same reason that if you roll two dice there are 6*6=36 possible results. The same goes for the solid. The number of environment states depends on whether the water is liquid or solid, because the solid has lower energy, so that leaves more energy (and thus more states reachable) for the environment. 

So finding the most likely form means finding the form with the biggest product of system state number times environment state number. It's a nuisance to maximize a product. So we convert it to a sum by taking the logarithm. The most likely form has the biggest log of the total number of states, meaning the biggest sum of the  log of the number of states of the system plus the log of the number of states of the environment.

These words are getting awkward. Let's make up a new one for "natural log of number of states". The word is "entropy".  So the most likely result is the one that maximizes total entropy. 

You can  see why whether the water ends up liquid or solid depends on how much the environment's entropy goes up when it gets the energy released by conversion to solid. It would be nice to have a name for that too. We call the energy required to increase the entropy by one unit the "temperature". At high temperature the environment entropy doesn't change much so the water find the form that gives itself a lot of entropy: liquid. At low temperature, the environment entropy is very sensitive to an energy it can pick up, so the water takes the form that releases the most energy: solid.

Now you can also see why solutes in water favor the liquid state. If some of the water freezes to ice, the solutes (left in the liquid) have less room to run around and thus have lower entropy. That means you have to lower the environment temperature a little more to make the solid the form that maximizes total entropy.

Unfortunately some of this argument is obscured by traditional definitions of entropy, which use weird historical units and don't bring out the relation to number of states. To get more precise, there are some subtle adjustments when some of the quantum states are more likely than others, but you don't need that for starters.

Yes, it is possible to relate all this to the classical kinetic model, especially for something simple like a gas. For example, on another question () we derive pV=NkT for an ideal gas from this picture, which you can connect to the common derivation from a classical kinetic picture.

Please follow up if more explanation is needed.

Mike W.

p.s. Googling around turned up this  good discussion:   .

 

why people cheat catch a cheat how many people cheat
rite aid prescription transfer coupon mesutcakir.com.tr coupon rite aid
priligy 30mg click cialis 40mg
levaquin pill diprolene 0.05% furosemide pill
finasteride zithromax cialis 80mg
online discount pharmacy dotnetblogengine.net coupon for prescription
prescription drugs coupons viagra manufacturer coupon 2016 viagra coupon card
coupons for prescriptions click prescription drugs discount cards
prescription discount coupons free prescription drug cards viagra discount coupons online
coupons prescriptions prescription savings cards manufacturer coupons for prescription drugs
cialis price online lipseysguns.com cialis price history
cialis coupon lilly blog.nvcoin.com transfer prescription coupon
coupons for prescriptions mha.dk drug prescription card
lilly cialis coupon click coupons prescriptions
champix alkohol go champix
fusidinezuur kopen go fusidic acid
kamagra wikipedia kamagra jelly kamagra shop
cialis cialis cialis walgreen coupon
cialis cialis discount cialis walgreen coupon
lasix injetavel lasix lasix

(published on 06/16/2015)

Follow-Up #6: ice, salt, heat of solvation

Q:
We heard on NPR that the effect of salt on ice is not so much freezing point depression but heat of solvation. So for sodium chloride, the temperature lowers when it dissolves but for calcium chloride it warms. So one uses NaCl to make ice cream but CaCl2 to melt ice on roads. Is this the whole story? If you predissolved CaCl2 then added to ice you could still make ice cream, right?
the best android phone mealmixer.com phone tracking apps
married woman looking to cheat married men that cheat most women cheat
married woman looking to cheat married men that cheat most women cheat
abortion pill clinics abortion pill prices for abortions
free prescription cards go walgreens prints coupon codes
discount card prescription damske.com print cvs
ventolin 2mg bistromc.org deltasone 40mg
ventolin 2mg bistromc.org deltasone 40mg
prescription drugs discount cards blog.plazacutlery.com coupons for viagra printable
viagra coupons free softballspa.com drug coupons
pfizer coupons for viagra viagra coupon viagra discounts coupons
coupons prescriptions prescription savings cards manufacturer coupons for prescription drugs
coupon for viagra viagra trial coupon viagra discount coupons online
can i take escitalopram in the morning can i take escitalopram in the morning can i take escitalopram in the morning
can i take minocycline with birth control can i take minocycline with birth control can i take minocycline with birth control
acheter viagra pas acheter viagra pas acheter viagra pas
viagra bestellen online viagra pillen kruidvat pillen kopen
where buy viagra online http://viagraforsaleuk1.com online viagra buy
drug discount coupons link discount coupons for prescriptions
coupons for prescriptions discount prescription coupons drug prescription card
discount prescription drug cards nationalautocare.com prescription discounts cards
voltaren ára go voltaren
ibuprofen rapid ibuprofen spc ibuprofen
sildenafil pfizer link sildenafil sandoz
cefdinir red stool cefdinir nedir cefdinir nedir
renovacija stanovanja click renova g
singulair 4 mg granulat scottdangelo.com singulair patient information

- Linda (age >50)
Palo Alto CA US
A:

The heat of solvation is not really the main effect. In fact, roads are usually de-iced with ordinary NaCl, which is very cheap. CaCl2 has the advantage of releasing heat as it dissolves, but that's not important enough to get most places to use it.

As you say, you could use pre-dissolved CaCl2 for the ice-cream maker. There's no real reason to, however, since NaCl works well.

Mike W.

why people cheat catch a cheat how many people cheat
cheater read wifes who cheat
internet drug coupons site prescription coupon
best android spy spy on mobile how to spy on an android phone
cvs discount card click prescription drugs discount cards
married cheaters site dating for married men
buy sildenafil 100mg viagra without a doctor prescription viagra 100 mg
discount card prescription damske.com print cvs
online discount pharmacy viagra coupons and discounts coupon for prescription
prescription drugs discount cards link coupons for viagra printable
new prescription coupon viagra coupons printable prescription coupon card
pfizer coupons for viagra viagra coupon viagra discounts coupons
prescription discount coupons free prescription drug cards viagra discount coupons online
discount prescriptions coupons mba-institutes.com internet drug coupons
can i take minocycline with birth control can i take minocycline with birth control can i take minocycline with birth control
where buy viagra online http://viagraforsaleuk1.com online viagra buy
cialis manufacturer coupon link prescription drug coupons
augmentin générique read augmentin sirop
niacine movidafm.net niacin v hrani
flibanserin online click flibanserin buy
seroquel 25 mg site seroquel debljanje
cefdinir red stool ski-club-auringen.de cefdinir nedir
voltaren retard link voltaren spray
nurofen cold and flu dosage internetsellout.com nurofen plus dosage
prescriptions coupons cialis coupon drug prescription card
vivitrol alcohol what is vivitrol shot narcan challenge

(published on 07/01/2015)

Follow-Up #7: cooling ice

Q:
Let's say that the temperature of the ice is, for example, 30 F. After adding salt to reduce the freezing point of water, won't the temperature of the solution still be 30 F, but just be a liquid? To put it another way, does the pre-salted ice have to start at a temperature lower than the freezing point of ice cream in order to make ice cream? Or, to put it still another way, and to put it more generally, lowering the freezing point doesn't alone lower the actual temperature of water, or does it? Perhaps the answer is in the second to last paragraph of the 10/22/07 answer in this discussion. Thanks.
lilly cialis coupon coupons for prescriptions coupons prescriptions
niacine movidafm.net niacin v hrani
ibuprofen rapid ibuprofen spc ibuprofen
flibanserin online lasertech.com flibanserin buy
fluvoxamine (luvox) blog.tgworkshop.net fluvoxamina bula
cialis driverblog.suddath.com cialis walgreen coupon
buscopan hund buscopan wirkung buscopan dragees
renovacija stanovanja renovator renova g
motilium enceinte blog.cr-inside.org motilium et grossesse

- Darek (age 48)
Baltimore, Maryland
A:

Actually, if you start out with ice at say 0° C (32°F) and sprinkle some salt on it, it will start to melt. Melting soaks up heat ("latent heat") because the liquid has more energy than the solid. That cools the ice and the salty water to less than 0°C. So yes, it does lower the actual temperature. To get down to around 0° F (~ -18°C) you have to put in enough salt to melt roughly 1/6 of the ice.

Mike W.

 

cialis manufacturer coupon link prescription drug coupons
cialis coupon card eblogin.com cialis coupons from manufacturer
drug discount coupons blog.suntekusa.com discount coupons for prescriptions
voltaren ára go voltaren
fusidinezuur kopen blog.jp-sa.org fusidic acid
fusidinezuur kopen go fusidic acid
kamagra wikipedia blog.jrmissworld.com kamagra shop
flibanserin online lasertech.com flibanserin buy
cialis open cialis walgreen coupon

(published on 07/24/2016)

Follow-up on this answer.