Five groups of students in Mr. Walker's science class performed an experiment to determine the effect of salt on the boiling point of water. Each group dissolved 5g of salt in 100mL of distilled water, heated the solution and recorded the boiling point with a thermometer that had divisions of 0.1°C.
Each group obtained exactly same boiling point for the salt solution, 100.8°C. Are the results valid?
A) No, because too little salt was used.
B)No, because it was not a controlled experiment.
C)Yes, because each group obtained the same results.
D)Yes, because the thermometer had divisions of 0.1°C.