Bitte hängen Sie den Mantel auf den Kleiderbügel und schließen Sie den Reißverschluss ganz.

Because Sie here means you in the formal sense.

German has:

• du = you, informal, one person
• ihr = you, informal, more than one person
• Sie = you, formal, one or more people

The capital letter helps distinguish formal Sie from sie, which can mean she or they.

So Bitte hängen Sie ... is a polite instruction, like:

• Please hang ...
• Please close ...

This is the formal imperative.

For formal commands in German, the pattern is:

infinitive + Sie

So:

• Hängen Sie ...
• Schließen Sie ...

That is different from the informal imperative:

• Häng den Mantel auf! = informal, to one person
• Schließt den Reißverschluss! = informal, to more than one person

So the sentence is using the polite command form.

Yes. The full verb is aufhängen, meaning to hang up.

German has many separable-prefix verbs. In a main clause, the prefix often moves to the end:

• Ich hänge den Mantel auf.
• Hängen Sie den Mantel auf.

So in your sentence:

• hängen = the main verb part
• auf = the separable prefix, placed at the end of that clause

This is very common in German:

• anmachen → Machen Sie das Licht an.
• zumachen → Machen Sie die Tür zu.

Because Mantel is a masculine noun (der Mantel) and here it is the direct object of the verb aufhängen.

The direct object takes the accusative case.

So:

• nominative: der Mantel
• accusative: den Mantel

You are doing the action to the coat, so it becomes den Mantel.

Because this phrase expresses movement toward a destination, not a static location.

German two-way prepositions like auf use:

• accusative for direction / movement to
• dative for location / position

Here, the coat is being moved onto the hanger:

• auf den Kleiderbügel = onto the hanger

Compare:

• Der Mantel hängt auf dem Kleiderbügel. = The coat is hanging on the hanger.
  (location, so dative)
• Hängen Sie den Mantel auf den Kleiderbügel. = Hang the coat onto the hanger.
  (direction, so accusative)

Because Kleiderbügel is masculine: der Kleiderbügel.

After auf in a directional sense, German uses the accusative, so:

• der Kleiderbügel → den Kleiderbügel

So both den Mantel and den Kleiderbügel are accusative, but for different reasons:

• den Mantel = direct object of the verb
• den Kleiderbügel = object of auf showing direction

German often combines nouns into a single compound noun.

Kleiderbügel is made from:

• Kleider = clothes
• Bügel = hanger / frame / bar

So Kleiderbügel literally means something like clothes hanger, which in natural English is coat hanger or clothes hanger.

This is very normal in German:

• Haustür = house door = front door
• Zahnbürste = tooth brush = toothbrush
• Reißverschluss = rip fastener = zipper

Literally, it breaks down like this:

• reißen = to tear / rip
• Verschluss = closure / fastener

So Reißverschluss literally means something like rip-closure or zip fastener, but the normal English meaning is simply zipper.

Like many German compound words, the literal parts help you remember it, even if the natural translation is just one everyday English word.

Here ganz means completely or all the way.

So:

• schließen Sie den Reißverschluss ganz = close the zipper completely
• more natural English: zip it all the way up

It does not mean whole here. It is acting as an adverb, modifying schließen.

You may also hear:

• ganz öffnen = open completely
• ganz zu = fully shut

German often places adverbs like ganz later in the clause, especially when they modify the whole action.

So:

• Schließen Sie den Reißverschluss ganz.

sounds natural and means Close the zipper completely.

German word order is often more flexible than English, but some positions sound more natural than others. In this sentence, putting ganz at the end is very idiomatic.

Because there are really two coordinated commands:

1. Hängen Sie den Mantel auf den Kleiderbügel
2. schließen Sie den Reißverschluss ganz

Each part has its own verb, so each formal imperative normally includes Sie.

You might think of it as:

• Please hang the coat on the hanger and please close the zipper completely.

German usually keeps that structure clear.

Sometimes learners expect an den Kleiderbügel, because in English we often say hang something on a hanger.

But in German, auf einen Kleiderbügel hängen is very common and idiomatic for placing clothing onto a hanger.

Very roughly:

• auf einen Bügel hängen = put onto a hanger
• an einen Haken hängen = hang on a hook

So the choice of preposition often depends on the object and the usual German expression, not just a one-to-one English match.

No, it is not grammatically required, but it makes the command more polite.

Compare:

• Hängen Sie den Mantel auf. = Hang up the coat.
• Bitte hängen Sie den Mantel auf. = Please hang up the coat.

Since the sentence already uses formal Sie, adding Bitte makes it sound even more polite or service-oriented.

Yes, it is perfectly understandable and natural, especially in instructions.

That said, in everyday speech a native speaker might also say things like:

• Bitte hängen Sie den Mantel auf einen Bügel.
• Bitte hängen Sie den Mantel auf den Bügel.
• Bitte machen Sie den Reißverschluss ganz zu.

So your sentence is good German, but there can be small variations depending on context and speaker preference.