What happens in space with out a suit?

In the low pressure environment, gas exchange in the lungs would continue as normal but would result in the removal of all gases, including oxygen, from the bloodstream. After 9 to 12 seconds, the deoxygenated blood would reach the brain, and loss of consciousness would result. Death would gradually follow after two minutes of exposure - though the limits are uncertain. If actions are taken quickly, and normal pressure restored within around 90 seconds, the victim may well make a full recovery.

Humans exposed to vacuum will lose consciousness after a few seconds and die of hypoxia within minutes, but the symptoms are not nearly as graphic as commonly shown in pop culture. Blood and other body fluids do boil when their pressure drops below 6.3 kPa, (47 torr) the vapour pressure of water at body temperature. This condition is called ebullism. The steam may bloat the body to twice its normal size and slow circulation, but tissues are elastic and porous enough to prevent rupture. Ebullism is slowed by the pressure containment of blood vessels, so some blood remains liquid.

Rapid evaporative cooling of the skin will create frost, particularly in the mouth, but this is not a significant hazard.

Rapid decompression can be much more dangerous than vacuum exposure itself. Even if the victim does not hold his breath, venting through the windpipe may be too slow to prevent the fatal rupture of the delicate alveoli of the lungs. Eardrums and sinuses may be ruptured by rapid decompression, soft tissues may bruise and seep blood, and the stress of shock will accelerate oxygen consumption leading to hypoxia. Injuries caused by rapid decompression are called barotrauma. A pressure drop as small as 13 kPa (100 torr), which produces no symptoms if it is gradual, may be fatal if occurs suddenly.

Actually, having an oxygen supply over your nose and mouth and the rest of you still being exposed to vacuum would be MORE dangerous than being entirely exposed to the vacuum with no oxygen supply at all.

Although vacuum exposure WOULD be able to kill you by asphyxiation eventually, what kills you faster in practice is that the lack of pressure causes dissolved gases to start bubbling out of your blood fluid, bringing on terrible circulatory problems. You get about ten seconds of consciousness, and if you're recompressed under about the one-minute mark you can make a full recovery. After that, you start getting permanent tissue damage, and you'd be dead after about three minutes of continuous exposure.

However, this is assuming you're smart enough to let the air out of your lungs. If you don't do that, the pressure differential causes your lungs to rupture, which means severe, probably fatal damage almost immediately. Having the oxygen mask strapped over your face would prevent you from letting the air out, meaning that, far from keeping you alive longer, the pressure of the oxygen supply pushing through your mouth and windpipe into your lungs would actually kill you faster.

EDIT: There seems to be a VERY common misconception that space is 'cold' and somehow causes you to freeze. This is completely false. Vacuum is actually a rather good insulator of heat, and you wouldn't cool down in space all that much faster than in your everyday environment (and it would be faster only because your sweat would be evaporating faster; if not for that, you would actually cool down SLOWER in space).

Not much longer. The real problem isn't oxygen, it's air pressure.

Without the constant pressure of air pushing down on us, our bodies would expand and balloon out because of gasses inside us that would suddenly be able to push out. Eventually we would be blobs of matter.

You've done a lot of research, but haven't discovered this question gets asked, and answered, twice a day here. That really is some research. While you typed in your question, you didn't see that on the left side of your screen the big letters that said "WAIT YOUR QUESTION MAY HAVE ALREADY BEEN ASKED"?

You would freeze solid instantly.

Depends on what planet you're on. But in general, space is either to hot or to cold to live. That's what the suit assists in is the blocking of the heat or coldness.

I really don't think it matters.. You will oxygen slowly instead just your body shutting down instantly..

You would get embarrassed, seriously.

Plus your body would be exposed to the ambient temperature of space.

If you happened to be near to the sun, that would result in radiation burns.

If you were were far from the sun you would freeze.