Students are investigating bone composition in their anatomy lab. They have been supplied with chicken bones and are soaking the bones in vinegar (acid), bleach (base), and water for 48 hours. It is hypothesized
that
changing the pH of the solution will cause a change in the composition of the bone. They mass the bones at 0,
24, and 48 hours and record observations in their data table. After 48 hours, this is the data they have collected.
Why did the students soak one of the bones in water?
A)
this is the control group
B)
this is the dependent variable
this is the independent variable
D)
to test the effects of different solutions