Mini Cosmetic Chemistry Lessons

Mini Cosmetic Chemistry Course Exam

Section A: Multiple Choice Questions (1 mark each)

1. What is the main purpose of an emulsifier in cosmetics?
   a) Add fragrance
   b) Mix oil and water together
   c) Preserve the product
   d) Add colour
2. Which ingredient is commonly used as a humectant?
   a) Beeswax
   b) Glycerine
   c) Coconut Oil
   d) Titanium Dioxide
3. What does pH measure?
   a) Thickness of a product
   b) Colour intensity
   c) Acidity or alkalinity
   d) Shelf life
4. Which phase contains oils, butters, and waxes?
   a) Water Phase
   b) Cool Down Phase
   c) Oil Phase
   d) Preservative Phase
5. What is the role of a preservative in skincare products?
   a) Increase foam
   b) Prevent microbial growth
   c) Add shine
   d) Improve fragrance
6. Which ingredient is a surfactant?
   a) Shea Butter
   b) SCI
   c) Vitamin E
   d) Beeswax
7. Why is distilled water preferred in formulations?
   a) It smells better
   b) It is cheaper
   c) It reduces contamination risks
   d) It thickens products
8. What is an emulsion?
   a) A powdered ingredient
   b) A fragrance blend
   c) A mixture of oil and water phases
   d) A preservative system
9. Which ingredient category helps thicken products?
   a) Chelators
   b) Thickeners
   c) Humectants
   d) Fragrances
10. Which factor can affect product stability?
    a) Temperature
    b) Ingredient compatibility
    c) Storage conditions
    d) All of the above

Section B: True or False (1 mark each)

1. Water-based products do not require preservatives.
2. Essential oils can change the scent and function of products.
3. pH is important only for soaps.
4. Heating phases incorrectly can affect stability.
5. More fragrance always means a better product.
6. Cosmetic formulations should be measured accurately.
7. Microbial growth can occur in water-containing products.
8. Surfactants are used only in shampoos.
9. Emulsions can separate if poorly formulated.
10. Cosmetic chemistry requires safety practices.

Section C: Short Answer Questions (5 marks each)

1. Explain the difference between a humectant, emollient, and occlusive ingredient.
2. Why is pH important in skincare formulations?
3. List three reasons why formulations fail.
4. Explain the purpose of preservatives and why they are important.
5. Describe the three common phases in cosmetic formulation.
6. Name three safety practices when making cosmetic products.

Section D: Calculations and Formulation Questions

1. You need to make 500g lotion containing 8% oil. How many grams of oil are required?
2. A formula requires 2% preservative in a 250g batch. Calculate the preservative amount.
3. Convert the following percentages into grams for a 100g batch:

• Water: 65%
• Oil: 20%
• Emulsifier: 8%
• Humectant: 5%
• Preservative: 2%

1. If your product pH is too high, what actions could you take?

Section E: Practical / Scenario Questions

1. Your lotion separated after 24 hours. Give four possible reasons.
2. A customer wants a gentle body wash for dry skin. What ingredient categories would you include and why?
3. A foaming scrub becomes watery after 3 weeks. Suggest possible causes and solutions.
4. Explain how you would test product stability.
5. Why is accurate record keeping important in formulation?

Bonus Question (10 marks)

1. Design a basic moisturising lotion formula using ingredient categories only (not percentages). Explain the purpose of each ingredient category.

Total: 100 Marks