Chemistry & ElectricityPregunta 82 de 100
Which statement about emulsions used in skin care is accurate?
a.An emulsion is a single pure substance with no separate phases
b.An emulsion is a mixture of oil and water held together by a surfactant, and it may be oil-in-water or water-in-oil
c.All emulsions are water-in-oil and feel heavy on the skin
d.Emulsions do not require an emulsifying agent
Explicación
An emulsion suspends one immiscible liquid inside another, and a surfactant or emulsifier keeps the droplets dispersed so the product does not separate. Oil-in-water emulsions feel lighter and are common in lotions, while water-in-oil emulsions are richer and more occlusive. Without an emulsifier the phases separate, and an emulsion is by definition a mixture, not a pure substance.
Practica las 100 preguntas gratis — sin registro.
Preguntas relacionadas de este tema
- A product label states a pH of 3.5. What does this tell the esthetician?
- A client with dehydrated skin should look for which type of ingredient to attract and bind water in the skin?
- How do alpha hydroxy acids (AHAs) differ functionally from beta hydroxy acid (salicylic acid)?
- A client develops itching, redness, and small bumps only where a new serum was applied, appearing about a day after use. What is the most likely explanation and correct action?
- An esthetician plans a galvanic desincrustation treatment. Which statement is correct?
- Before using a high-frequency device, which precaution is most important?
Última revisión: · proceso editorial
Equipo Editorial de PrepPass · Verificado con California Esthetician Written Licensing Exam · Cómo revisamos