Breaking Bad is known for its airtight plotting and attention to technical details. Here at Slate, it’s been called “TV’s Best Medical Drama Ever” for its realism, and The New Yorker has called its depiction of the meth trade “uncannily accurate.” The show’s scientific advisor, chemistry professor Donna Nelson, frequently gives interviews about the science behind the show, bolstering its reputation for verisimilitude.

But it’s worth remembering that at the end of the day Breaking Bad is still pulp (anyone who thinks otherwise is on meth), and pulp written and produced by human beings. Below, we’ve rounded up 10 of the blunders that keep the show from quite achieving flawlessness.

Mild spoilers ahead.

1. There is no chemical element “Ch.”

This was fixed in later episodes:

2. Pure meth isn’t blue.

From Breaking Bad’s own science consultant, in an interview with Scientific American:

What Walt is supposedly synthesizing is powder blue. I can tell you the pure crystals I made never looked anything like that. I don’t think that’s realistic.

(It’s more likely the Heisenberg meth would be clear or faintly yellow.)

3. Osama bin Laden wasn’t killed until 2011.

In an interview with Slate, showrunner Vince Gilligan acknowledged an inconsistency in the timeline of the show, pointed out by a writer:

The writer said to me: “I thought this show took place in 2007, and it’s only been a year since then, but last week you had someone mention the Osama Bin Laden assassination. How do you reconcile that?” I had to say, “Well, honestly, I don’t.”

4. A lot of the Spanish accents are terrible.

I’ll let Slate’s Juliana Jiménez, a native Spanish speaker, explain:

The Terrible Spanish accents amount to perhaps the most egregious flaw in the show. Really, they couldn’t find actors who actually speak Spanish? Gus’s accent was one of the worst—it didn’t sound remotely Chilean, and in fact it barely sounded like Spanish at all—and he was one of the most important characters on the show! Misplaced intonations, random pauses, choppy flow… it was one of the most unintentionally awkward Spanish accents I’ve heard on television, and not for lack of competition.

5. Hydrofluoric acid would not eat through a bathtub.

Walt and Jesse’s method of disposing of bodies is real—in Mexico, it’s called the guiso, or “stew” —but MythBusters has shown that no amount of hydrofluoric acid would have eaten through that tub.

6. No one’s aim is that bad.

In one of the show’s most climactic moments, the standoff at the end of “To’hajiilee,” eight gunmen all take aim, unleash a firestorm of bullets, and all miss. This is improbable at best. While the accuracy rate of trained law enforcement can drop as low as 18 percent in firefights, scores if not hundreds of shots were fired before anyone got hit.

7. You can sometimes see the crew.

8. And there are continuity errors.

9. Meth doesn’t make you hallucinate.

In Season 1, Jesse smokes meth and has an elaborate hallucination: He sees two Mormon missionaries as hulking bikers armed with a sword.

But as former meth addict and dealer James Salant pointed out in GQ, “Meth does not induce hallucinations. It is not a hallucinogen.”

10. The chemistry doesn’t always add up.

Scientific errors go all the way back to the pilot, as chemist Jonathan Hare pointed out for the BBC:

In one scene, in their makeshift mobile meth lab out in the desert, Walt is being threatened by two gangsters. He improvises a method to gas them by throwing red phosphorus into hot water. … He later explains to Jesse that this reaction produced poisonous phosphine gas. Red phosphorus can react with hydrogen to produce phosphine—but not with hot water.

Of course, since Breaking Bad is pulp, perhaps it’s OK for it to make up its own laws of chemistry.

Read all of Slate’s Breaking Bad coverage.