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Balancing Cr with H+

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dogman:
Hello ya'll! First time here =)
Feel like this is a pretty noob question, but honestly, I am tripping over this for days.
I was given very little information:

"The metal chromium (Cr) reacts with an acid to produce Cr+3 and hydrogen gas. Write the balanced reaction."

Yeah, that's really it. I was also given the tip that the acid is related to H+, and the reaction may produce water-vapor.

Any ideas? :) Someone suggested to me to think about "half-reactions" when considering this topic, but I didn't really manage to get what they meant.

EDIT:
I apologize, I didn't explain my issue here well enough: My problem with the question is that I have no idea with which reagents I am working with. The way the question is phrased, makes it look like the equation is just : "Cr + H+", and that can't be right, and a follow-up question highly suggests there is water involved somehow.
Anyone have any idea what else might be at play here, that was intentionally left out by my lecturer?

Orcio_87:

--- Quote ---"The metal chromium (Cr) reacts with an acid to produce Cr+3 and hydrogen gas. Write the balanced reaction."

Yeah, that's really it. I was also given the tip that the acid is related to H+, and the reaction may produce water-vapor.
--- End quote ---
Water can by the side-product if Cr2O3 is used instead of the Cr. But here it is clear - Cr and acid products Cr3+ and hydrogen gas.

Corribus:
It's a little vague but for sake of simplicity let's assume the acid is dissociated. In that case, the counterion - call it A- - is inconsequential (a spectator) and you only have to worry about the H+. But, your post indicates you may not yet know what how to describe an acid in reaction formalism so ask for clarification if you find that confusing.

So why not start with the basics? Do you know how to write a(ny) chemical reaction? I.e., what goes on the left and what goes on the right. And do you know how to balance chemical reactions? If the answer is "yes", then you just have to put the reactants and products where they go and make sure all the charges and atoms are equal on both sides.

dogman:
Hey, cheers spending some time on this :p
I feel like I failed to properly elaborate what my problem with the question was, because I do have the basics down, but the question itself was defined so vaguely, probably on purpose, that I just need some help on clearing out the fog...

And that's to say, with which reagents am I working here? I mean, is my equation truly just:
"Cr + H+"? That can't be right, can it? I'm sure there's more going on, that's not explicitly written. :s It's implied that there is water involved in a follow-up question, but it's not explicit.

EDIT: A friend of mine noted that "water can't be part of the equation, metals and acid produce "salt" and hydrogen gas. The 'water' can only be the source of the acid. I assume you need to add an equation of the water's-breakdown to H3O+ and OH-"
I am translating from another language, so the terms are most likely incorrect, sorry about that. <:
Any thoughts on how this might lead me to the initial equation, to this incredibly vague question?

Orcio_87:

--- Quote ---And that's to say, with which reagents am I working here? I mean, is my equation truly just:
"Cr + H+"? That can't be right, can it? I'm sure there's more going on, that's not explicitly written.
--- End quote ---
Did you heard about the oxidation-reduction reactions ?

Here H+ is an oxidant and the Cr is the reductant. You don't need anything else.

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