El escáner hace menos ruido que la impresora, pero tarda más en escanear.

Yes, in Spanish it is very common to use the definite article with nouns when talking about things in a general or specific context.

• el escáner = the scanner
• la impresora = the printer

In this sentence, the speaker is comparing two specific devices, so the articles sound natural and expected.

English often drops the in general statements, but Spanish usually keeps the article more often.

Both are possible, but they mean slightly different things in tone.

• hace menos ruido = makes less noise
• es menos ruidoso = is less noisy

Spanish often uses hacer ruido as a very natural expression for to make noise. In everyday speech, this is probably the most common way to express the idea.

So:

• El escáner hace menos ruido que la impresora sounds very natural.
• El escáner es menos ruidoso que la impresora is also correct, but a bit more descriptive and adjective-based.

menos ... que means less ... than.

Structure:

• menos + noun + que
• menos + adjective/adverb + que

In this sentence:

• menos ruido que la impresora = less noise than the printer

More examples:

• Tiene menos paciencia que yo. = He/She has less patience than me.
• Corre menos rápido que su hermano. = He/She runs less fast than his/her brother.

It is the direct opposite of más ... que = more ... than.

Spanish often expresses this idea with tardar más = to take more time.

So:

• tarda más literally means it takes more
• natural English translation: it takes longer

This is just a difference in how the two languages package the idea.

Compare:

• Tarda más en escanear. = It takes longer to scan.
• Tarda menos en arrancar. = It takes less time to start up.

Because tardar is commonly followed by en + infinitive when you say how long something takes to do an action.

Pattern:

• tardar + cantidad de tiempo + en + infinitive
• or simply tardar + más/menos + en + infinitive

Examples:

• Tardo dos horas en terminarlo. = I take two hours to finish it.
• La impresora tarda mucho en calentarse. = The printer takes a long time to warm up.
• El escáner tarda más en escanear. = The scanner takes longer to scan.

So en is the normal preposition here.

Yes. They are directly related:

• escáner = scanner (the machine)
• escanear = to scan (the action)

Both words come from English, but they have been adapted to Spanish spelling and pronunciation.

Notice the accent mark in escáner. It shows where the stress goes: es-CÁ-ner.

Because pero means but, and it connects two contrasting ideas:

• El escáner hace menos ruido que la impresora
• pero tarda más en escanear

The comma helps separate the two clauses, just like in English many similar sentences do:

• The scanner makes less noise than the printer, but it takes longer to scan.

In Spanish, using a comma before pero in this kind of sentence is standard.

Because Spanish often leaves out the subject when it is already clear from context.

The sentence could be written more fully as:

• El escáner hace menos ruido que la impresora, pero el escáner tarda más en escanear.

But that sounds repetitive. Since we already know the topic is el escáner, Spanish naturally omits it:

• ..., pero tarda más en escanear.

This is very common in Spanish because the verb form often gives enough information, and context does the rest.

Usually, no extra verb is needed here.

Spanish normally says:

• hace menos ruido que la impresora

That already means makes less noise than the printer.

If you said:

• hace menos ruido que la impresora hace

it would sound unnecessary and awkward in most contexts.

Spanish generally avoids repeating the verb when the comparison is already clear.

Because pero is used for simple contrast, while sino usually follows a negative statement and corrects it.

Here we have:

• The scanner makes less noise than the printer, but it takes longer to scan.

That is a contrast between two true ideas, so pero is correct.

Examples:

• Es pequeño, pero rápido. = It is small, but fast.

Use sino in sentences like:

• No es una impresora, sino un escáner. = It isn’t a printer, but rather a scanner.

So in your sentence, pero is the right conjunction.

Exactly. The present tense here describes a normal, general fact about the scanner and printer.

• hace = present tense of hacer
• tarda = present tense of tardar

This is like saying:

• The scanner makes less noise
• The scanner takes longer to scan

It is not about one single moment only; it sounds like a general comparison between the two devices.