A group of students designed an experiment to investigate the factors that influence the corrosion (rusting) of iron. Identical iron nails were placed in 5 different test tubes under the conditions described below:
* Tube 1: Nail fully submerged in of distilled water, with a layer of mineral oil on top to prevent contact with atmospheric oxygen.
* Tube 2: Nail exposed to ambient air only (no liquid).
* Tube 3: Nail fully submerged in of distilled water exposed to ambient air.
* Tube 4: Nail fully submerged in of a (salt) solution exposed to ambient air.
* Tube 5: Nail fully submerged in of a acetic acid (vinegar) solution exposed to ambient air.
Match each test tube to its specific role in the experimental design.
- Tube 1The control group that isolates the role of oxygen by preventing air exposure while maintaining water exposure.
- Tube 2The control group that isolates the role of liquid water by eliminating liquid exposure while maintaining air exposure.
- Tube 3The baseline group representing standard conditions (water and air) to which chemical treatments are compared.
Cevap
Tube 1 matches the control group that isolates the role of oxygen; Tube 2 matches the control group that isolates the role of liquid water; Tube 3 matches the baseline group representing standard conditions.
Matching the correct roles to each tube ensures that the independent variables (oxygen presence, water presence, and chemical treatments) are properly isolated. Tube 1, which has water but no oxygen, is the control for oxygen's role. Tube 2, which has air but no water, is the control for water's role. Tube 3, which has both water and air under standard conditions, is the baseline group for comparison with active chemical treatments.
Adım Adım Çözüm
Anahtar Kavram
Determining Control Groups and Baseline Conditions
Tahmini Süre:1m 30s