Presentation on theme: "STEM Project Safe in the Sun. Why is Sun Screen Important?"— Presentation transcript:
STEM Project Safe in the Sun
Why is Sun Screen Important?
STEM Project Safe in the Sun The sun produces lots of different types of rays, some you can see and some you can't It is some of those you can't see that do the damage
STEM Project Sun Screen A bottle of sun cream does not contain just one substance. It is a mixture of lots of ingredients, each doing an important job. One of the main ingredients has the job of stopping too much harmful ultraviolet from reaching the skin. But, there's problem!
Safe in the Sun Activity 7 – Lumps or Powder?
STEM Project Grant is one of our scientists In our factory we make an ingredient that is used in sun protection cream. When this ingredient is made it’s in the form of big white lumps, but we cannot use these lumps in our recipe.
STEM Project Lumps or Powder? When this main ingredient arrives from the factory where it is made it comes as large lumps. To make the sun cream, however, this needs to be a powder, like this photograph shows Why do you think it needs to be a powder?
STEM Project Lumps or Powder The powder in sun screen is expensive, so we’ll use different types of sugar in oil You need to predict & test which type would be best for a sun screen How will we make our experiment a fair test? Who will do what in your groups?
STEM Project Roles & Responsibilities Administrator keeps a written and pictorial record for the group Resource Manager collects, sets up and returns all equipment used by the group Communications Officer collects the group’s ideas and reports back to the rest of the class. Health and Safety Manager takes responsibility for the safety of the group, making sure everyone is working sensibly with the equipment Personnel Manager takes responsibility for resolving disputes within the group and ensuring the team works together
STEM Project You will need 4 plastic cups of different types of sugar Cubes Caster Granulated Icing 4 plastic measuring cups with red lids 4 plastic spoons 1 timer
Safe in the Sun Activity 8 – Grinding Solids
STEM Project Grinding Solids As we know, the sun screen active ingredient arrives in lumps and needs to be ground into a powder Can you find the best material to grind up sugar lumps into powder? How can we make it a fair test?
STEM Project You will need Marbles Ball bearings Smarties / beans 3 pots with lids 3 sugar cubes Weighing scales (shared between the class)
Safe in the Sun Activity 9 – Testing Sunscreens
STEM Project You will need UV beads Small samples of sunscreen A, B and C Tray 3 Plastic cups Teaspoon Pipette