Which of the following is NOT a consideration when determining the proper mixing of mortar?

When determining the proper mixing of mortar, one of the most critical aspects is ensuring that the mix achieves the right consistency. Consistency affects how well the mortar adheres to the masonry units and how workable it is during application. Additionally, using clean water is fundamental since contaminants can alter the properties of the mortar and affect curing and bonding.

Specified materials refer to the exact types of cement, sand, lime, and other additives required in the mix. Adhering to these specifications ensures that the mortar will perform as expected for the project.

In contrast, the use of reactant chemicals is not a standard consideration in traditional mortar mixing for masonry. While certain specialized mortars may involve chemical additives to enhance specific properties, typical mortar mixing does not account for chemicals that react in the manner implied here. Therefore, focusing instead on consistency, clean water, and specified materials aligns with standard practices for mixing mortar in masonry projects.