In class we did a lab on making crayons float in water. My team chose to change the sizes of the crayons. They were 2cm, 4cm, and 6cm. We put each crayon in the water one at a time and used spoonfuls of salt to see how many spoonfuls it took to make each sized crayon float.
As the size of the crayon increases the amount of salt will increase because as the crayons get bigger it will take more salt to make it float.
Here were our results:
it took 2 spoonfuls of salt to make the 2cm crayon float
it took 3 spoonfuls of salt to make the 4cm crayon float
and it took 4 spoonfuls of salt to make the 6cm crayon float
As the amount of salt changed, the different sized crayons floated with different amounts of salt. This was confusing because each crayon had the same density, which means it should have taken the same amount of salt to make each crayon float. Our prediction was correct. The highest data point was 4 spoonfuls to make the 6cm crayon float. The lowest data point was 2 spoonfuls to make the 2cm crayon float. An uncertainty was that the crayons floated with different amounts of salt. I wonder what would happen if we used iodized salt.