Learn Hardcore Spanish (Latin America): En el laboratorio de química todos usan gafas de protección. - In the chemistry lab everyone wears safety glasses.

En el laboratorio = in the lab (a specific lab, “the lab”)
Saying en laboratorio sounds incomplete or very unusual; it would only appear in special technical/telegraphic styles (e.g., labels, headlines), not in normal speech.

So when you say in the X in Spanish, you usually need en + el/la + place:

en la escuela – in (the) school
en el trabajo – at work
en el laboratorio – in the lab

What does “de química” really mean in “laboratorio de química”?

De química is like saying “of chemistry” or “chemistry” as an adjective:

laboratorio de química = chemistry lab / laboratory of chemistry

Spanish often uses noun + de + noun where English uses noun + noun:

clase de matemáticas – math class
libro de historia – history book
laboratorio de química – chemistry lab

Why is it “todos usan” and not “todo el mundo usa”?

Both are possible, but they are slightly different:

todos usan = everyone wears / they all wear
todo el mundo usa = literally the whole world uses, but it means everybody wears

Todos is shorter and more neutral here. Todo el mundo is also very common in conversation, but todos is perfectly natural and a bit more direct.

Why is “todos” plural but in English it’s “everyone wears” (singular)?

Spanish and English treat this idea differently:

Spanish: todos usan
- todos = “all (people)”, grammatically plural
- verb: usan (3rd person plural)
English: everyone wears
- everyone is grammatically singular
- verb: wears (3rd person singular)

So Spanish says literally “all [of them] use” (plural), while English says “everyone uses” (singular).

Why is the verb “usan” and not something like “llevan”?

Both can be correct, but there’s a nuance:

usar gafas de protección = to use / wear protective glasses (focus on using them as equipment)
llevar gafas de protección = to wear protective glasses (focus on carrying/wearing them on your face/body)

In many contexts, usar and llevar overlap when talking about clothing/accessories. In a lab context, usar feels slightly more technical, like “use protective equipment.”

Why is it “usan gafas de protección” without an article (no las or unas) before gafas?

In Spanish, when talking about what people generally wear/use (clothes, accessories, protective gear), you can often omit the article:

Todos usan gafas de protección. – Everyone wears safety goggles.
En esta empresa usamos uniforme. – In this company we wear a uniform.

You can say unas gafas de protección, but it slightly emphasizes “some (a pair of) protective glasses” in a more specific way.

Here the idea is general: in that lab, protective glasses are the standard equipment, so no article is needed.

What exactly does “gafas de protección” mean? Why “de protección” and not an adjective?

Gafas de protección literally means “glasses/goggles for protection”:

gafas – glasses / goggles
de protección – for protection / of protection

Spanish often uses de + noun to express purpose or function:

gafas de sol – sunglasses (glasses for sun)
zapatos de trabajo – work shoes
casco de seguridad – safety helmet

You could see gafas protectoras, with an adjective, but gafas de protección (or gafas de seguridad) is more natural for safety equipment.

Is “gafas” the usual word in Latin America, or do they use something else?

In much of Latin America, speakers more often say:

lentes de protección / lentes de seguridad
anteojos de protección (in some countries)

Gafas is fully correct and understood everywhere, but it’s more typical of Spain. In a Latin American context, you’d probably hear:

En el laboratorio de química todos usan lentes de seguridad.

Why is it “usan gafas de protección” and not “usan las gafas de protección”?

With objects used in a general/habitual way, Spanish often omits the definite article:

Todos usan gafas de protección. – People wear safety goggles (as a rule).

Las gafas de protección would suggest specific goggles already known in the context:

En esa caja están las gafas de protección. – The safety goggles are in that box.

In the sentence you gave, we’re talking about the practice in general, not about a specific pair of goggles.

Why is it the present tense “usan” and not something like “están usando”?

Spanish present tense (usan) is used both for:

Habitual actions
- En el laboratorio de química todos usan gafas de protección.
  = In the chemistry lab, they wear (as a rule) safety goggles.
Actions happening now (with context)
- Ahora todos usan gafas de protección.
  = Right now they are all wearing safety goggles.

If you say están usando, you emphasize what they’re doing right now:

En este momento, todos están usando gafas de protección. – Right now, everyone is using/wearing them.

Your sentence describes a rule/habit, so usan is the best choice.

Can “todos” go in a different place in the sentence?

Yes. Common possibilities:

Todos usan gafas de protección en el laboratorio de química.
En el laboratorio de química, todos usan gafas de protección. ✅ (your version)
En el laboratorio de química, usan gafas de protección todos. (possible, but unusual and more emphatic or poetic)

The most natural are the first two, with todos before the verb.

Why is it “de química” and not “químico” (like laboratorio químico)?

laboratorio de química = lab where chemistry is studied or done
laboratorio químico sounds more like “chemical laboratory” (emphasizing that the lab itself is chemical in nature, or belongs to a chemical company)

For school/university contexts, the normal phrase is laboratorio de química = chemistry lab.

Is there any difference between “En el laboratorio de química todos usan gafas de protección” and starting with “Todos”?

Both are correct and natural:

En el laboratorio de química todos usan gafas de protección.
- First focuses on place, then the rule.
Todos usan gafas de protección en el laboratorio de química.
- First focuses on everyone, then where.

The meaning is essentially the same; it’s just a matter of emphasis and flow.