What happens to building materials that are subjected to efflorescence?

When building materials experience efflorescence, a chemical reaction occurs whereby soluble salts and moisture migrate to the surface of the material, typically due to water infiltration. As the moisture evaporates, it leaves behind these salts, resulting in a white, powdery residue. Over time, the accumulation of these salts can lead to an increase in internal pressure within the material, which can cause it to crack and, in severe cases, break apart. This degradation is particularly problematic in masonry, concrete, and similar materials where structural integrity is crucial. Thus, the correct answer indicates that the materials involved may indeed break apart due to the stresses caused by efflorescence.