What Changes Occur During Sublimation? It's More Than Just Magic

Understanding Sublimation: A Rare Phase Transition

Sublimation is that fascinating process where a substance skips the liquid phase entirely and goes straight from solid to gas. No melting. No dripping. Just—poof—gone into vapor. You’ve probably seen it with dry ice, right? It looks like it’s "smoking," but really, it’s sublimating. That cloud isn't smoke—it's cold carbon dioxide gas condensing water vapor from the air.

Scientifically speaking, sublimation occurs when the vapor pressure of a solid exceeds atmospheric pressure at a given temperature, allowing molecules to break free directly into gas form.

Physical Changes That Take Place

Phase Shift: Solid to Gas, Clean Cut

Unlike melting (solid → liquid) or evaporation (liquid → gas), sublimation skips the middle step. It’s a direct energy leap, which means the particles in the solid gain just enough kinetic energy to overcome intermolecular forces and go airborne.

• No liquid state involved

• Molecules rearrange from tight-packed to freely moving

• Example: frozen CO₂ (dry ice) turns directly into CO₂ gas at −78.5°C

Energy Absorption: Endothermic by Nature

Sublimation requires energy—it’s endothermic. The substance absorbs heat from its surroundings, even if you don’t feel it (sometimes it's freezing to the touch because it pulls heat from your skin).

Oh, and here's a thing: that energy isn't "used up" in heating the material—it goes into breaking molecular bonds. That’s called the latent heat of sublimation. Yeah, fancy word, but key idea.

Chemical Composition: Does It Change?

Nope. The chemical identity stays the same. Solid iodine becomes iodine vapor. Solid CO₂ becomes gaseous CO₂. Nothing is broken or chemically altered—it’s all about physical state, not structure.

But! If the temperature gets too high during sublimation, some substances might decompose instead of subliming. That’s a whole other story (and not technically sublimation anymore).

Real-World Examples of Sublimation

In Nature and Daily Life

• Snow in dry cold weather can disappear without melting. That’s sublimation.

• Mothballs (naphthalene) slowly vanish in your closet? Also sublimation.

• Frozen laundry left outside on a cold sunny day can dry. Water sublimates right off the ice crystals.

There was this one time during a hike in the Alps—middle of winter, minus 10 or something—and the snow on the rocks just started thinning out even though it was way below freezing. At first I thought it was melting. Nope, it was sun-powered sublimation. Wild stuff.

Industrial Applications

• Freeze-drying (lyophilization): Removes water by sublimation to preserve food or vaccines.

• Sublimation printing: Uses heat to turn dye into gas that bonds with fabric—great for vivid colors.

Conditions Required for Sublimation

It doesn’t happen just anywhere. Sublimation usually needs:

• Low atmospheric pressure (like high altitudes or controlled chambers)

• Sufficient heat energy to let molecules escape directly from the solid

• A substance that’s volatile enough to sublimate instead of melting

Water ice, for example, will sublimate in space (where there's vacuum), but not so much in your kitchen freezer.

Final Thoughts: It’s All About the Energy Game

So yeah, sublimation is kind of a show-off among phase transitions. It bends the rules, does its own thing, and demands just the right mix of pressure and heat. But it’s not magic—it’s pure thermodynamics.

At first, I thought it was just some quirky thing that only dry ice did. But the more you look, the more you realize it’s all around us—quietly changing solids into vapor without anyone really noticing. That’s... kind of poetic, honestly.

Is 165 cm normal for a 15 year old?

The predicted height for a female, based on your parents heights, is 155 to 165cm. Most 15 year old girls are nearly done growing. I was too. It's a very normal height for a girl.

Is 160 cm too tall for a 12 year old?

How Tall Should a 12 Year Old Be? We can only speak to national average heights here in North America, whereby, a 12 year old girl would be between 137 cm to 162 cm tall (4-1/2 to 5-1/3 feet). A 12 year old boy should be between 137 cm to 160 cm tall (4-1/2 to 5-1/4 feet).

How tall is a average 15 year old?

Average Height to Weight for Teenage Boys - 13 to 20 Years

How to get taller at 18?

Staying physically active is even more essential from childhood to grow and improve overall health. But taking it up even in adulthood can help you add a few inches to your height. Strength-building exercises, yoga, jumping rope, and biking all can help to increase your flexibility and grow a few inches taller.

Is 5.7 a good height for a 15 year old boy?

Generally speaking, the average height for 15 year olds girls is 62.9 inches (or 159.7 cm). On the other hand, teen boys at the age of 15 have a much higher average height, which is 67.0 inches (or 170.1 cm).

Can you grow between 16 and 18?

Most girls stop growing taller by age 14 or 15. However, after their early teenage growth spurt, boys continue gaining height at a gradual pace until around 18. Note that some kids will stop growing earlier and others may keep growing a year or two more.

Can you grow 1 cm after 17?

Even with a healthy diet, most people's height won't increase after age 18 to 20. The graph below shows the rate of growth from birth to age 20. As you can see, the growth lines fall to zero between ages 18 and 20 ( 7 , 8 ). The reason why your height stops increasing is your bones, specifically your growth plates.