Is hence used porperly in the following sentence?

I wouldn't use it that way, rather say "hence his mission is complete", except that I've never actually heard anyone use "hence", to my knowledge. It's not a word you're gonna hear in everyday conversation. Or even in everyyear conversation. Try "so" instead.

I use "hence."

I'm not surprised.

Make sure you use the legal kind

You can also use it when you're in the mood to be slightly german.

"Ze chicken house ist poppenziekorken und ist brokken up in ze high vind. Hence all over ze place".

That is just telling him to use informal or casual language always. He is not asking how to chat with a guy in a bar. Many people use 'hence' and are familiar with it. Used as a synonym for 'therefore' it comes before the thing alleged to be the consequence or conclusion:

It’s that India has an airline that is run by politicians and hence can be milked by various interest groups.

Used to mean 'from here' (distance) or 'from now' or 'from that time' it comes after the distance or period or time:

We are nearly home. London is five miles hence. (Obsolete or poetic)

In the 14th century, belief in witchcraft was widespread, but now, seven centuries hence, it has almost vanished.

When I die, hopefully some decades hence, I will leave you all of my money.

Although it's not that common, i also use hence conversationally. Contrex has covered all the bases on its usage as far as i can see.

Is hence used porperly .properly in the following sentence?

By the way, the word was neither used "porperly," nor was it used properly--it should not have followed the clause.

whence?

Thence.

I choose this answer!

Laughed til my sides hurt!

I think you're confusing it with 'hemp.'

Hence means from whither.

Also used in the Schuhplattler song Hence, Kneece und Boompsi-daisi.

No, contrex, it's not. Most people probably know what it means, but it's not commonly used, setanta aside, and it's another of those words that sounds fairly stilted when used

Damn, you all are a riot!

Well, when I use it, it sounds extremely appropriate.

Can anyone help me with my problem?

Not if you keep it to yourself.