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See, it's funny because atoms are really small.

Go ahead, imagine the smallest thing you can think of, the smallest thing you can see.

That's made of more atoms than there are people on Earth.

It's made of more atoms than there are grains of sand on the planet.

Atoms are smaller than you think.

Watch as I turn water into phenolphthalein's basic form!

See, it's funny because most kids would not be excited about the magician being replaced by a scientist.

Then again, the experiment mentioned in the final panel does look pretty cool.

You're part of the precipitate.

See, it's funny because the word solution here means a mixture of a solute (the blue, solid material) and a solvent (the clear or white liquid, assumedly and frequently water). Solution can also mean a resolution to some problem.

See, so making a solution was the solution.

Lick a snozzberry

See, it's funny because sniffing many of the elements would be terribly dangerous.

Some would just be unpleasant: selenium, sulfur, perhaps osmium.

This one isn't exactly too deep.

Shardik would be fine

See, it's funny because the bear in the water is a polar bear.

In chemistry, polar means one side of the species (molecule, usually) has a slight positive charge, and the other side a slight negative charge. This means the polar molecule will attract to water which is also polar.

Non-polar bears (brown bears, black bear, spectacled bears, koala bears, gummi bears) wouldn't dissolve in water.

Though they should be careful about swimming in cyclohexane because it's non-polar, so non-polar solutes would dissolve in it.

Been there...

See, it's funny because boiling pure hydrochloric acid would be awful for the room's occupants.

Admittedly, though, pure hydrochloric acid has a boiling point of -85 C, so it's already a gas at room temperature.

The student might be boiling a solution of hydrochloric acid - which does create an awful smell, something I know from a lab that I do with my students each year in which they synthesize sodium chloride by mixing sodium carbonate and hydrochloric acid. Typically the acid is in excess, so when they boil away the water created, they usually get a very brief wiff of the chlorine gas at the end.

Ideally, it's a very small wiff.

Salty

See, it's funny because NaCl is the chemical formula for sodium chloride, typically known to most folks as table salt.

I would, however, take a half point off of the soup for having written the symbols in all upper-case letters.

It's NaCl not NACL.