Note: Answers for Q 9 and 10 are omitted because they depend on the current and local cost
for the ingredients.
Applying Your Knowledge
Why do you think salt was added to the ice? Adding salt to the ice lowers the freezing point to approximately –10°C. This creates an
environment for the cream (or milk) to freeze and form the ice cream.
Is ice cream a pure substance or a mixture? Ice cream is a mixture because it contains more than one substance. There is vanilla,
sugar, milk (fat, calcium, water, etc.).
Did a chemical or physical change take place during the preparation of ice cream?
How do you know? A physical change took place because the ingredients in the bag froze. A change of state
represents physical change.
The chemical formula for the sugar (sucrose) used in this activity is C12H22O11?
Is sucrose an element or a compound? Explain your answer. Sucrose is a compound because it is composed of 3 kinds of different elements - carbon,
hydrogen, and oxygen.
What common mineral is found in milk products (like ice cream) that is essential
for the growth of strong bones and teeth? Calcium is the common mineral found in milk products that is essential for the
growth of strong bones and teeth.
Write the chemical symbol of this mineral. The chemical symbol for calcium is Ca.
Where is this symbol located in the periodic table. Calcium is located in group II, the alkaline earth metals.
Why is it important to wash your hands and have a clean lab bench? To create a sterile environment and avoid bacterial contamination of the food.