Auf dem Weg zum Ausgang kaufe ich am Kiosk noch eine Birne und eine kleine Tüte Chips.

Because German uses the verb-second rule in main clauses. The finite verb must come in the second position.

Here, the first position is taken by the whole phrase Auf dem Weg zum Ausgang. So the verb kaufe has to come next, and the subject ich comes after it:

• Auf dem Weg zum Ausgang = position 1
• kaufe = position 2
• ich = subject after the verb

You could also say:

• Ich kaufe auf dem Weg zum Ausgang am Kiosk noch eine Birne und eine kleine Tüte Chips.

That is also grammatical, but the original sentence puts more emphasis on the setting: on the way to the exit.

Because auf is a two-way preposition, so it can take either:

• dative for location
• accusative for movement toward a destination

In auf dem Weg, the phrase is idiomatic and means on the way. It uses the dative:

• der Weg → dem Weg (dative singular)

Compare:

• auf dem Weg = on the way
• sich auf den Weg machen = to set off, to get going

So in this sentence, auf dem Weg is the normal expression for on the way.

Zum is a contraction of zu dem:

• zu dem → zum

The preposition zu takes the dative, so:

• der Ausgang → dem Ausgang
• zu dem Ausgang → zum Ausgang

So auf dem Weg zum Ausgang literally means on the way to the exit.

Am is a contraction of an dem:

• an dem → am

Here it means at the kiosk. Since this is a location, German uses the dative:

• der Kiosk → dem Kiosk

So:

• am Kiosk = at the kiosk

Here noch means something like:

• still
• also
• one more thing before leaving
• in addition

In this sentence, it gives the idea that before the speaker finally leaves, they also buy something else:

• ... kaufe ich am Kiosk noch eine Birne ...
• ... I also buy a pear at the kiosk / I still buy a pear ...

It often adds a small sense of before that’s over or in addition.

They are both in the accusative because they are the direct objects of kaufen.

You buy something, so kaufen takes an accusative object.

• eine Birne = accusative feminine singular
• eine kleine Tüte Chips = accusative feminine singular

Both Birne and Tüte are feminine nouns, and in the accusative singular feminine, the article is still eine.

Because it comes after the article eine, and the noun Tüte is:

• feminine
• singular
• accusative

So the correct form is:

• eine kleine Tüte

This is part of German adjective endings. After an ein-word like eine, the adjective takes the ending that fits the gender/case pattern here, which is -e.

Compare:

• eine kleine Tüte = feminine accusative singular
• ein kleiner Kiosk = masculine nominative singular
• einen kleinen Kiosk = masculine accusative singular

Because eine Tüte Chips is a quantity expression: a bag of chips.

In German, after words like:

• eine Tüte (a bag)
• eine Flasche (a bottle)
• eine Packung (a pack)
• ein Glas (a glass)

the thing inside often appears without an article:

• eine Tüte Chips
• eine Flasche Wasser
• eine Packung Kekse

So Chips here works a bit like the contents of the bag.

The head noun is Tüte:

• eine kleine Tüte = a small bag

Then Chips tells you what kind of bag it is:

• eine kleine Tüte Chips = a small bag of chips

So grammatically, the phrase is centered on Tüte, not on Chips. That is why the article and adjective agree with Tüte, not with Chips.

No. Birne can mean several things depending on context, including:

• pear
• light bulb
• informally, head

But in this sentence, because the speaker is buying something at a kiosk together with chips, eine Birne clearly means a pear.

Not always, especially if you are thinking of British English.

In German, Chips usually means potato chips / crisps, not fries.

So:

• German Chips = American chips = British crisps
• German Pommes or Pommes frites = fries / British chips

So in this sentence, eine kleine Tüte Chips means a small bag of potato chips/crisps.

Because this is just an introductory prepositional phrase, and in German that normally does not need a comma.

So this is correct:

• Auf dem Weg zum Ausgang kaufe ich ...

A comma would usually only appear if there were a more complex inserted structure or a subordinate clause, not a simple opening phrase like this one.

Because German capitalizes all nouns.

In this sentence, the nouns are:

• Weg
• Ausgang
• Kiosk
• Birne
• Tüte
• Chips

That is why they all begin with capital letters. This is a standard rule in German spelling.