Which compounds primarily cause temporary hardness in water used for brewing?

Temporary hardness in water is primarily attributed to the presence of calcium and magnesium ions. These ions can dissolve in water from naturally occurring minerals and contribute to the hardness of the water. When water contains these cations, it forms bicarbonates, which can precipitate out of solution when heated. This phenomenon is known as temporary hardness because it can be removed by boiling the water, which causes the bicarbonate to convert into insoluble carbonates that can then be filtered out.

In brewing, the hardness of the water can impact the overall brewing process, including extraction efficiency and flavor profile of the beer. By understanding the role of calcium and magnesium ions, brewers can manipulate water profiles to achieve desired characteristics in the final product.

The other options do not contribute to temporary hardness. Chloride and sulfate ions, while they can influence flavor and other aspects of brewing, do not affect the hardness in a temporary manner. Nitrate and nitrite ions are typically associated with other water quality concerns, such as pollution, rather than hardness. Finally, sodium and potassium ions generally relate to the salinity of the water rather than its hardness. Therefore, calcium and magnesium ions are the correct and primary contributors to temporary hardness in brewing water.