Final answer:
Three conditions must be met for limestone and dolostone to precipitate from seawater: the presence of dissolved calcium carbonate and magnesium carbonate in the seawater, a decrease in pH, and an increase in temperature or pressure.
Step-by-step explanation:
In order for limestone and dolostone to precipitate from seawater, three conditions must be met:
- The presence of dissolved calcium carbonate and magnesium carbonate in the seawater.
- A decrease in pH, caused by factors such as the escape of carbon dioxide or the addition of an acid.
- An increase in temperature or pressure, which can trigger the precipitation of calcium carbonate and magnesium carbonate as limestone and dolostone.