- Mindful moment.
- Review previous DSN entry.
- Preview blogpost for today.
- Create new DSN entry for today.
- Data from 3 classes replicating the demonstration of mixing 50 ml water with 50 ml ethanol. (Make sure your name appears)
- Proposed explanations. (Make sure your name appears).
Today–develop/select an explanation for observations made when water and ethanol are mixed. Then develop and implement a procedure(s) to test the explanation. A scientific experiment is a test of a suspected explanation.
- “Vanished volume.” Many would expect 100 ml but every attempt we made was noticeably less.
- Increased temperature. Every attempt we made showed a noticeable increase in temperature–above the ambient temperature.
- Bubbles. Tiny bubbles appear when the two liquids are mixed.
- “Mixing lines.” Even though both liquids are clear, when they are mixed the light refracts differently in each liquid and “lines” or blurry areas of movement appear.
If the explanation you develop/select is true, then there should be certain consequences in addition to what you have already observed. Find out if those consequences actually happen. If they clearly do, then you have support for the possible explanation. If they clearly do not, then the explanation is seriously challenged. Either approach is valued in science–finding corroborative (supporting) evidence or finding evidence that “rules out.”
Work carefully and neatly. Keep your area tidy. Keep dispensing areas tidy. Wear eye protection. Remember safety cautions for ethanol.
Record your observations, procedures, thoughts, etc. in your DSN. Label everything. Record data in tables with labels and units. The time you take now to get good records will save you time writing your report. It should be very easy to have thorough DSN entries for today.
Check in with Dr. F for your proposed tests/experiments–for safety, reasoning, and plausibility. You must clearly state the explanation. Cleary explain the procedure and how it relates to the suspected explanation. You must clearly say what you expect to happen if the explanation is true.