Learn Hardcore Portuguese (Portugal): Na cozinha, temos um pequeno contentor só para reciclagem de plástico. - In the kitchen we have a small container just for plastic recycling.

em + a = na → na cozinha = in the kitchen
You cannot say em a cozinha; in standard Portuguese this must contract to na.
Similarly:
- em + o = no (no quarto = in the bedroom)
- em + as = nas (nas casas = in the houses)
- em + os = nos (nos carros = in the cars)

Could I also say Temos um pequeno contentor na cozinha? Is the word order important?

Yes, you can say both:

Na cozinha, temos um pequeno contentor…
Temos um pequeno contentor na cozinha…

Both are correct. The difference is emphasis:

Na cozinha, temos… puts a little emphasis on where (in the kitchen).
Temos um pequeno contentor na cozinha… is a more neutral order: first what we have, then where.

The comma after Na cozinha is normal, but in a short sentence like this you might also see it written without the comma in informal contexts.

Why is it temos and not há or existe?

temos = we have (1st person plural of ter).
há = there is / there are (impersonal form of haver).
existe / existem = there exists / there exist.

So:

Na cozinha, temos um pequeno contentor… = In the kitchen, we have a small container…
→ Focus on we (the speakers) possessing/using it.

You could also say:

Na cozinha, há um pequeno contentor… = In the kitchen, there is a small container…
→ More neutral, just stating existence in that place.

All three verbs are possible in the language, but temos explicitly includes the speakers.

Why is it um pequeno contentor and not um contentor pequeno? Where do adjectives usually go?

Both orders are grammatically correct:

um pequeno contentor
um contentor pequeno

In Portuguese, adjectives usually come after the noun, but many common adjectives (like grande, pequeno, bom, mau) can appear before or after with slight differences in feel:

um pequeno contentor
- Quite normal and maybe a bit more “default” with pequeno.
- Slightly more integrated, almost like one concept: a small-container (as a type).
um contentor pequeno
- Feels a little more descriptive or contrastive, like you’re distinguishing it from a bigger container: a container (which is small).

In everyday speech, um pequeno contentor is very natural in European Portuguese.

What does contentor mean here, and are there other words I could use?

In this sentence, contentor means a container or bin (for rubbish or recycling).

Common alternatives in European Portuguese:

caixote do lixo = rubbish bin / trash can (general trash)
caixote da reciclagem = recycling bin
balde do lixo = bucket-style trash bin
contentor do lixo / contentor de reciclagem = larger bins, often used outside or for building/communal use

Here, um pequeno contentor só para reciclagem de plástico suggests a small bin or container specifically used for plastic recycling, probably inside the kitchen.

What does só mean in só para reciclagem de plástico? Could I use apenas or somente?

In this sentence, só is an adverb meaning only:

só para reciclagem de plástico = only for plastic recycling

It does not mean lonely here; that sense of só appears in contexts like estou só (I’m alone).

You could also say:

apenas para reciclagem de plástico
somente para reciclagem de plástico

All three (só, apenas, somente) are fine. só is the most informal and most frequent in speech. apenas and somente sound a bit more formal or careful.

Why is it para reciclagem de plástico and not para reciclar plástico?

Both are possible, but they have slightly different structures:

para reciclagem de plástico
- reciclagem = recycling (noun)
- Literally: for recycling of plastic
- Focus on the purpose or function: the container is a recycling container.
para reciclar plástico
- reciclar = to recycle (verb)
- Literally: to recycle plastic
- Focus more on the action (what you do with it).

In this context, para reciclagem de plástico sounds very natural because we’re describing a type of bin (a plastic-recycling bin).
para reciclar plástico is also correct and understood, just expressed with a verb instead of a noun.

Why is it reciclagem de plástico instead of reciclagem do plástico?

reciclagem de plástico = recycling of plastic (plastic in general, as a material)
reciclagem do plástico = recycling of the plastic (more specific)

Using de without the article often refers to something in general or as a type of material:

reciclagem de vidro (glass)
reciclagem de papel (paper)
reciclagem de plástico (plastic)

If you say reciclagem do plástico, it tends to sound like:

a specific plastic previously mentioned, or
the recycling of plastic as a known, defined process (more abstract or technical).

For a simple label on a bin or everyday description, reciclagem de plástico is the standard choice.

Why is plástico singular here and not plásticos?

plástico here is used as an uncountable material noun, like glass, wood, paper in English:

reciclagem de plástico = recycling of plastic (the material)

If you say reciclagem de plásticos (plural), it suggests:

different types of plastic, or
many individual plastic items.

In everyday speech, for a bin that takes any plastic items, reciclagem de plástico (singular) is extremely common and natural.

Could I say para a reciclagem de plástico instead of para reciclagem de plástico?

Yes, you can, and it’s still correct:

só para reciclagem de plástico
só para a reciclagem de plástico

The version with the article (para a reciclagem…) can sound:

a bit more formal or specific (e.g. referring to the established recycling system),
more like a particular process: for the recycling of plastic.

The version without the article is very common in fixed expressions about use or function:

saco para lixo (bag for rubbish)
contentor para reciclagem de plástico (container for plastic recycling)

So in this kind of everyday description, para reciclagem de plástico (without a) feels slightly more natural, but both are acceptable.

How do I know that contentor is masculine? How does that affect the other words?

You can see it from the words that agree with it:

um (masculine singular article)
pequeno (masculine singular adjective)
contentor (noun they agree with)

So contentor is masculine: o contentor, um contentor.

General patterns (not 100% rules):

Nouns ending in -o are often masculine.
Nouns ending in -or are often masculine too (e.g. o motor, o elevador, o contentor).

If it were feminine, you’d see:

uma pequena caixa (a small box)
uma pequena lata (a small can)

The article (um/uma) and adjective (pequeno/pequena) must match the gender and number of the noun.

Is the comma after Na cozinha necessary?

The comma is optional but normal here.

Na cozinha, temos um pequeno contentor…
→ The comma separates an introductory location phrase, slightly pausing after Na cozinha.

You could also see:

Na cozinha temos um pequeno contentor…

Both are fine. With short, simple sentences, many writers omit the comma. With longer or more complex sentences, the comma becomes more important for clarity.

How should I pronounce the tricky words like cozinha, contentor, só and reciclagem in European Portuguese?

Very approximate English-like guides (European Portuguese):

cozinha → co-ZEE-nyə
- z like z in zoo
- nh like ny in canyon
- final a is a reduced sound, like an unstressed uh.
contentor → kon-ten-TOR
- Stress on the last syllable: tor.
- Final r in European Portuguese is often a guttural sound in the throat.
só → saw (but short)
- The accent on ó keeps the vowel open.
- It’s a short, stressed syllable.
reciclagem → roughly hɾɨ-see-KLA-zheng
- Initial r is often a guttural sound (like a French r).
- ge in -gem is like the s in measure (zh sound), plus a nasal ending (air goes through the nose).

These are approximations, but they should help you get close to the European Portuguese sounds.