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Snack Attack

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					            creativeminds                                             Investigate!

        Snack Attack
Recent medical research claims that too much salt is bad for
your health.

You have a range of snack food and as a health scientist, have to find
out which snacks contain the most salt.

You have:
A variety of salted snacks e.g. crisps, savoury yeast snacks, mini cheese biscuits etc.
Hand lenses                  Filter paper Beakers      Filter funnels
Water Salt                   Scales                    Intel microscope if available

Activity
1.   If time, search internet to find salt information.

2.   Discuss how and why salt is added to snack food (coating on crisps, ingredient in
     baked snacks). Look at snacks with hand lenses to see salt. Can we measure salt
     levels this way?

3.   How can we extract salt from snacks? Demonstrate salt dissolving in water if
     necessary. Use filtration to extract salt from snacks. Discuss how to make this a fair
     test e.g. constant weight/volume, does volume of water added matter?

4.   Leave solution in the beakers to evaporate and then weigh beakers against a
     control to establish salt levels in snacks. This could be evaluated visually.
     Encourage scientific vocabulary.

Explanation
The salt in the snacks will dissolve in the water and can be filtered and separated from
the snacks. When the water evaporates the amount of salt per mass of cereal can be
calculated. The snacks produce more salt if crushed and mixed with warm water.

Useful Questions
•    What is happening to the salt?
•    How can we get the salt back from the water?
•    What happens to the water in the beakers, where does it go?
•    Why does the weight/volume of snacks used matter?
•    Could we improve this test?
•    How do we know the crystals produced are salt?
                creativeminds                                                     Investigate!


 Extension Activities
 •     Plot a graph to compare amount of salt per 100g of product. Does this match the
       manufacturer's claims?
 •     Repeat test several times to get average salt value. Why should we do this?
       Compare different brands of the same snack.

 Research Opportunities
 •     How is salt manufactured?
 •     Are there different types of salt?
 •     How does salt preserve food and why is it necessary to do this?
 •     How does sea life cope with living in a salty environment?

 Useful Websites
 www.salt.gov.uk

 www.walkers.co.uk




                                    The Creative Minds project works with museums libraries and
                                   archives across the Yorkshire region, to provide young people with
                                   learning opportunities in Science, Technology, Engineering & Maths
(S.T.E.M.). This ground-breaking project is the first of its
kind in the country and is managed by MLA Yorkshire. This
pack was developed by Creative Minds and Eureka! The
Museum for Children with funding from Yorkshire Forward.

				
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