Also depends on what material the mold is on. Sometimes it "digs" down in. Bleech won't get depp in and kill it. Go to Home Depot or such and tell them you have mold on the wall and what type of wall (painted, concrete, drywall, etc.) and they'll get you the right stuff.
If it's on drywall, I suggest scratching down in to the board a few places to see how far it goes. If it goes more than a quarter of the way, you need to replace the material. Sucks I know, but it'll come back even if you treat it. Especially if it's all the way through, then it'll just grow on the backside and spread behind it.
If it's black mold, it is likely in the air too. It'll spread all over the place. Get a hepa airfilter in the room and change out your HVAC filter, then again in a few weeks.
As said before, don't do this without lots of fresh air flowing through. I know lots of contractors who do it, but then years later they wonder why they're hacking and wheezing. Chemicals can easily damage the lungs causing them to build up scar tissue. Open windows and shut the door to the room. Yes, even in the Winter. Bag anything used to scrap/wipe the mold off and seal it in ziplocks until it's out of your house/garage.
Chemical Pneumonia Overview
Chemical pneumonia is an unusual type of lung irritation. Pneumonia usually is caused by a bacteria or virus. In chemical pneumonia, inflammation of lung tissue is from poisons or toxins. Only a small percentage of pneumonias are caused by chemicals.
•Many substances can cause chemical pneumonia, including liquids, gases, and small particles, such as dust or fumes, also called particulate matter. Some chemicals only harm the lungs; however, some toxic materials affect other organs in addition to the lungs and can result in serious organ damage or death.
•Aspiration pneumonia is another form of chemical pneumonia. Aspiration means that you breathe oral secretions or stomach contents into your lungs. The inflammation comes from the toxic effects of stomach acid and enzymes on lung tissue. Bacteria from the stomach or mouth can also cause a bacterial pneumonia.
•Chemical pneumonia is only one type of lung inflammation. You can read about viral pneumonia and bacterial pneumonia in their own sections