In our last science lesson, Year Five successfully separated a mixture of sand and water by sieving to separate the large pieces of sand and then using filter paper to separate the smaller pieces of sand from the water.

This week, they were set the challenge of separating a mixture of salt and water. The salt had dissolved so we knew the particles were very small and a sieve would not work. Most groups suggested we used the filter paper and they set to work trying to separate the salt from the water. However, this method did not work. After discussion, the children concluded that the salt particles were so small that they passed through the filter paper!

One group suggested that we could evaporate the water and it might leave the salt behind. So, we have poured our salt solutions into petri dishes and we will wait to see what happens next…