Programme For International Student Assessment Pisa / Sample Science Passage 10: Lip Gloss


The table below contains two different recipes for cosmetics you can make yourself. 
The lipstick is harder than the lip gloss, which is soft and creamy. 

Lip gloss             Lipstick 
Ingredients:        Ingredients: 
5 g castor oil   -   5 g castor oil 
0.2 g beeswax  -  1 g beeswax 
0.2 g palm wax  - 1 g palm wax 
1 teaspoon of colouring substance 1 teaspoon of colouring substance  - 1 drop of food flavouring 1 drop of food flavouring 

Instructions (Lip Gloss):
Heat the oil and the waxes in a container
Then add the colouring substance mixture.

Instructions (Lipstick): 
Heat the oil and the waxes in a container  placed in hot water until you have an even placed in hot water until you have an even  mixture.
Then add the colouring substance  and the flavouring, and mix them in. and the flavouring, and mix them in. 



Oils and waxes are substances that will mix well together. Oils cannot be mixed with water, and waxes are not soluble in water. Which one of the following is most likely to happen if a lot of water is splashed into the lipstick mixture while it is being heated?

The mixture becomes firmer.
The mixture is hardly changed at all.
A creamier and softer mixture is produced.
Fatty lumps of the mixture float on the water.

When substances called emulsifiers are added, they allow oils and waxes to mix well with water. Why does soap and water remove lipstick?

The soap acts as an emulsifier and allows the water and lipstick to mix.
The soap and lipstick combine to form an emulsifier that mixes with the water.
Water contains an emulsifier that allows the soap and lipstick to mix.
Emulsifiers in the lipstick allow the soap and water to mix.