Associate Certified Entomologist (ACE) Practice Exam

What characterizes emulsifiable concentrates (EC) in pest management?

1. They are powder forms mixed with an active ingredient

2. They form a milky solution when mixed with water

3. They are ready-to-use sprays without agitation

4. They are solids that require drying before application

The correct answer is: They form a milky solution when mixed with water

Emulsifiable concentrates (EC) are characterized by their ability to form a milky solution when mixed with water. This property results from the emulsification of oil-based active ingredients in a surfactant that enables them to disperse in water. When water is added to an EC formulation, the active ingredients, which are typically oil-soluble, become suspended in the water, creating a stable emulsion. This is important for pest management as it allows for an effective distribution of the pesticide over the target area, ensuring thorough coverage and enhanced efficacy. The other options represent different formulations or characteristics that do not apply to emulsifiable concentrates. For instance, powders mixed with an active ingredient do not create the same emulsification effect. Ready-to-use sprays typically do not require mixing before application, which is contrary to the nature of ECs that must be mixed with water. Lastly, solids requiring drying before application do not describe emulsifiable concentrates, as ECs are liquids that are meant to be sprayed without needing to dry after application.