AP Chemistry 3.3 Structure and Arrangement of Atoms
AP Chemistry 3.3 Structure and Arrangement of Atoms. What is the direct conversion from a solid to a gas called?
|AP Chemistry||Breaking Bonds|
Structure and Arrangement of Atoms
|Test Prep||AP Chemistry|
emits from fog machines because carbon dioxide is a solid at low temperature.
When exposed to air, carbon dioxide immediately converts to a gas.
What is the direct conversion from a solid to a gas called?
And here are our potential answers...
This question is fairly straightforward, but just for fun, let’s look at all the different [Road sign for route to the answer]
phase transitions you might get thrown at you on a test.
Hopefully not literally. [Teacher throwing balled up paper at a student]
Matter exists in one of three states: solid, liquid, or gas.
The temperature of the matter and pressure on the matter will determine what state the
matter is in.
Matter can transition between states if the pressure or temperature of the matter changes, [Liquid pouring out of a soda bottle]
or if they’re standing in that one cool place where Utah, New Mexico, Arizona, and
The most common transitions we observe in daily life are solid to liquid and liquid
to gas, because these are the transitions that water undergoes at normal temperatures [Man sitting on a sofa with a water droplet]
If these are not the transitions you observe most frequently, you may be a life form from [People standing in a field and alien appears from a spacecraft]
another planet in which case please contact NASA so they can study you––no dissections
However, all matter can undergo a transition between any two phases of matter if the temperature [Girl throwing darts at a board]
and pressure are in the right spot.
The question is asking us about a transition from a solid to a gas, which isn’t common
in water on earth but is the norm for carbon dioxide. [A river streaming with water]
And because scientists like graphs...really, here’s a graph showing how much we like
graphs compared to other people….there’s a graphical way to represent phase transitions. [People studying a graph]
This helps us see how transitions between any states of matter can occur, while having
all the added fun of being a graph!
Creatively called a “phase transition diagram,”––what? [Boy with a phase transition diagram]
We like graphs, not thinking of creative names for them–– this plot shows the state of
matter for CO2, the molecule in the question.
Each line between states on the graph represents a point where if the temperature or pressure
changes, the carbon dioxide will go from one state to another.
This gives us a total of six ways that matter can change states, because each change is
Let’s take a look at what each change is called.
Going from solid to liquid is named “Thomas,” but goes by “Tom” for short. [Ice cubes melt into a puddle of water]
...Okay, it’s actually called melting, and going from liquid to solid is freezing.
Going from liquid to gas is boiling and going from gas to liquid is condensing [Person pours boiling water into a pan]
And going from solid to gas is sublimation and going from gas to solid is deposition
The question was asking what the transition from a solid to a gas is called, so the answer
is A. Sublimation. [Answer A circled green]
Answer B, melting is solid to liquid and answer D, boiling is liquid to gas.
And answer D, decomposition isn’t even a transition between states of matter, so we
can toss that one right into the compost bin. [Man throws decomposition into a compost bin]
We found the right answer and eliminated all the others, so our chemistry skills must be
...Whoops. [Chemistry skills explode]
We meant sublime.
Now we’ll never get those skills back...