Question: What Freezes Faster Cold Or Warm Water?

What freezes faster cold water or hot water?

Hot water can in fact freeze faster than cold water for a wide range of experimental conditions.

This phenomenon is extremely counterintuitive, and surprising even to most scientists, but it is in fact real.

The phenomenon that hot water may freeze faster than cold is often called the Mpemba effect..

Does salt water freeze faster?

While pure water freezes at 0°C (32°F), salt water needs to be colder before it freezes and so it usually takes longer to freeze. The more salt in the water, the lower the freezing point. … Often, salt is put on roads to melt ice.

Does hot water kill germs?

Hot water kills germs, though it has to be very hot According to WHO, temperatures of 140°F to 150°F are enough to kill most viruses, and boiling water makes it safe from pathogens like bacteria, viruses, and protozoa.

At what temp does ice melt?

32°FThe freezing point at which water — a liquid — turns to ice — a solid — is 32°F (0°C). Based on their experiments melting the crushed ice, at what temperature does ice melt to make water — what is the melting point of ice? 32°F (0°C).

Should I boil hot or cold water?

Cold water boils faster than hot water. There is, however, a good reason to use cold water instead of hot for cooking: hot water will contain more dissolved minerals from your pipes, which can give your food an off-flavor, particularly if you reduce the water a lot.

Does cold water heat up faster?

“Cold water does not boil faster than hot water. … As a result, cold water will be absorbing heat faster while it is still cold; once it gets up to the temperature of hot water, the heating rate slows down and from there it takes just as long to bring it to a boil as the water that was hot to begin with.

Does hot water kill germs better than cold?

In its medical literature, the Food and Drug Administration states that hot water comfortable enough for washing hands is not hot enough to kill bacteria, but is more effective than cold water because it removes oils from the hand that can harbor bacteria.

At what temperature does water sanitize?

Water temperature must be at least 180°F, but not greater than 200°F. At temperatures greater than 200°F, water vaporizes into steam before sanitization can occur. It is important to note that the surface temperature of the object being sanitized must be at 160°F for a long enough time to kill the bacteria.

Does saltwater freeze?

Ocean water freezes just like freshwater, but at lower temperatures. Fresh water freezes at 32 degrees Fahrenheit but seawater freezes at about 28.4 degrees Fahrenheit , because of the salt in it. When seawater freezes, however, the ice contains very little salt because only the water part freezes.

Why does water not freeze at 0 degrees?

In order for water to freeze to ice, it needs something to freeze onto to start the process. … But if your water is very pure and very still, there is nothing for the water molecules to crystallize onto. As a result, you can cool very pure water well below zero degrees Celsius without it freezing.

Does hot water freeze faster than cold water Mythbusters?

The Mpemba effect is a process in which hot water can freeze faster than cold water. The phenomenon is temperature-dependent.

What bacteria can survive in hot water?

Boiling does kill any bacteria active at the time, including E. coli and salmonella. But a number of survivalist species of bacteria are able to form inactive seedlike spores.

Does boiling water freeze faster than room temperature water?

Hot water freezes faster than cold, known as the Mpemba effect. … Evaporation is the strongest candidate to explain the Mpemba effect. As hot water placed in an open container begins to cool, the overall mass decreases as some of the water evaporates. With less water to freeze, the process can take less time.

Is the mpemba effect real?

The Mpemba effect is the name given to the assertion that it is quicker to cool water to a given temperature when the initial temperature is higher. … We conclude, somewhat sadly, that there is no evidence to support meaningful observations of the Mpemba effect.

Why do oceans not freeze?

Ocean water freezes at a lower temperature than freshwater. Fresh water freezes at 32 degrees Fahrenheit but seawater freezes at about 28.4 degrees Fahrenheit , because of the salt in it. When seawater freezes, however, the ice contains very little salt because only the water part freezes.

Which freezes faster salt water or sugar water?

Salt water did not freeze solid. Still partly a liquid. We concluded that different substances can make a difference in how fast water freezes. The sugar water froze the fastest.

Which type of water freezes the fastest?

As the video above explains, the phenomenon of hot water freezing faster than cold water is known as the Mpemba effect, named after Erasto Mpemba, a Tanzanian student who in 1963 was making ice cream as part of a school project.

Why do hot water pipes freeze first?

The Mpemba effect is the observation that warm water freezes more quickly than cold water. … Hence the faster freezing. Another is that warm water evaporates rapidly and since this is an endothermic process, it cools the water making it freeze more quickly.