Final answer:
Respiratory acidosis occurs when there is an excess of carbonic acid in the blood due to too much CO2. It can be caused by various factors such as pneumonia or heart failure.
Step-by-step explanation:
Respiratory acidosis occurs when the blood is overly acidic due to an excess of carbonic acid, resulting from too much CO2 in the blood. Respiratory acidosis can result from anything that interferes with respiration, such as pneumonia, emphysema, or congestive heart failure.