does dry ice melt?

Question

I know that dry ice sublimates when water is added to it. even very cold water. but is there a temperature at which it acutally melts? litterally going from solid to a liquid?

thanks guys! i get it now :)

Answer 1

frozen CO2 doesn't melt into a liquid, but rather evaporates directly into its gaseous form

Answer 2

By tweaking pressure and what not, you could make dry ice melt into a liquid, but normally, at one atmosphere pressure it changes directly to gas, a process called sublimation. Pressure is the factor here, not so much the temperature.
It is possible under pressure to superheat water ABOVE the boiling point. And when the pressure is suddenly released, the water will explode like dynamite! You can build quite an effective bomb with nothing but Oxygen, namely Liguid Oxygen sealed in a special thick glass tube. When heated even a small amount, it'll explode with tremendous force! But
this baby is rather volatile! Handle with care. Hahahaha!
Sodium is so volatile that it burns upon exposure to air. A little inventiveness can deduce from this a really nice triggering device for some devices.....

Answer 3

For every substance there is a combination of temperature and pressure called its triple point, where all three states co-exist. This is because boiling point goes up with increasing pressure, but melting point goes down with increasing pressure. The triple point is where the two graphs cross. At pressures below the triple point pressure (where the "melting point" would be hotter than the boiling point), sublimation occurs. At pressures above the triple point pressure, the melting point is cooler than the boiling point and so the substance can exist as a liquid.

The triple point of carbon dioxide (dry ice is just solid carbon dioxide) is 5.2 atmospheres and -56.4 deg C (=216.6 K). I.E., CO2 gas will liquefy if compressed above 5.2 atmospheres.

Answer 4

Dry ice sublimes because the atmospheric pressure is too low to force it to go liquid before it melts. CO2 liquid is used for some specialty cleaning operations where it is held under pressure, high enough pressure to make it liquid.

Answer 5

Dry ice is frozen carbon dioxide. A block of dry ice has a floor temperature of -109.3 stages Fahrenheit (-seventy 8.5 stages C). Dry ice additionally has the very super function of sublimation -- because it breaks down, it turns straight away into carbon dioxide gasoline fairly than a liquid. The super-chilly temperature and the sublimation function make dry ice great for refrigeration. CO2 has no liquid state at everyday Earth atmospheric pressures. in spite of the undeniable fact that Carbon dioxide has a vapor rigidity of 830 psi at 20 °C. In different words, if one places sturdy carbon dioxide in a closed field at room temperature, the carbon dioxide will ultimately convert to liquid and the rigidity above that liquid would be 830 psi (approximately fifty six instances everyday atmospheric rigidity). The rigidity will continuously be 830 psi as long as some liquid carbon dioxide is present interior the closed field, and at greater temperatures the rigidity would be even greater effective. So CO2 does have 3 states sturdy liquid & vapor. additionally as liquid CO2 alterations to a gasoline there will be condensation around the vessel wherein in is stored. subsequently H20... So streching issues a sprint i assume you should assert CO2 changing states "created water"... and it would nonetheless be moist. :)

Answer 6

There is not a temperature at which it goes from solid to liquid under normal pressure. It has to be under high pressure to do that. At about 5 times normal atmophereic pressure, it will melt in the "normal" way.

Answer 7

According to wikipedia.org, carbon dioxide only can liquidize at pressures of 5.1 atm or more; at normal pressure, it can only be solid or gas, which is why it sublimates. At that pressure, the melting point is -57 degrees Celsius.

Answer 8

Dry ice is frozen CO2 gas. The freezing temperature at normal sea level air pressure is -78.5 degrees C (-109.3 degrees F).

Answer 9

CO2 has a liquid phase only at high pressures. The CO2 in a fire extinguisher is in the liquid phase.