Nearly all chemical reactions will occur at common temperatures. Examples are the breakdown of many chemical explosives into more unstable compounds. Nitroglycerine is notorious. Old explosives are more dangerous (i.e., liable to be triggered to explode by very small disturbances) than more recently manufactured explosives. Rubber products also degrade as sulphur bonds induced during vulcanization revert; this is why old rubber bands and other rubber products soften and get sticky as they age.