🫧 Oil, water and soap: the whole packet

🫧 Oil, water and soap · 3rd–8th grade · 1 day of testing · free · 60 minutes a sitting

My days, if the fair is 14 days away

Count back from your fair day and write in each date. Fewer days than this? The jobs share days, in this order; nothing is skipped.

Dates from my teacher

• My question is due
• Testing starts
• My results table and graph are due
• My board is due

In this packet

1. 🗓️ My project plan
2. 💭 My hypothesis
3. 🧺 Change, measure, keep the same
4. 🪜 My steps
5. 📊 My results
6. 📓 My logbook
7. ✅ My conclusion
8. ✂️ Board titles to cut out
9. 🏅 The judge's questions and my certificate

If I change how much dish soap goes in, then how long the oil and water take to split back into two layers will ________________, because _____________________________________________

What I think will happen, in my own words:

4 levels × 3 tries at each = 12 tries in all. If anything you keep the same changes, you won't know which change made the difference.

What I need

• 🛢️ Cooking oil: a quarter cup
• 🚰 Water from the tap: a quarter cup
• 🫧 Dish soap
• 🌈 Food colouring: 1 drop, so the water is easy to see
• 🫙 A clear jar or tall glass: 1 with a tight lid
• 🥛 A measuring cup
• ⏱️ A stopwatch or a kitchen timer

Be safe: 🚫 Not food · 🧽 A bit messy

1. Pour a quarter cup of water and a quarter cup of oil into a clear jar with a lid.
2. Add one drop of food colouring, so the water layer is easy to see.
3. Screw the lid on tight and shake it 20 times.
4. Set it down, start the timer, and watch the side of the jar.
5. Stop the timer when a clear line shows between the oil and the water, and write it down.
6. If no line shows after 10 minutes, write 600 seconds and stop.
7. Shake and time it two more times.
8. Add 5 drops of dish soap and do three more shakes and timings.
9. Add soap up to 10 drops, then up to 20, and do three tries at each.
10. Find the mean time for each amount and draw a line graph.

Write each number in your results table the moment you measure it.

I changed: Drops of dish soap   I measured: how long the oil and water take to split back into two layers (seconds)

MY GRAPH (a line graph: drops of dish soap along the bottom, seconds up the side)

What I noticed: ______________________________________________

Write something every day you work on it, even the days you only gather things. More days? The three-page logbook prints from peabody.kids/science-fair/templates/logbook.

My hypothesis was ☐ right ☐ partly right ☐ not right.

I know because my numbers show:

What surprised me, or what might have gone wrong (7th and up):

Next time I would test:

Idea: Change a second thing: keep 10 drops of soap and shake 10, 20 and 40 times, and draw a line for how long it stays mixed.

1. What made you want to ask this question? Say something like: I wanted to know: does dish soap stop oil and water from separating?
2. What did you think would happen, and why? Say something like: I thought changing how much dish soap goes in would change how long the oil and water take to split back into two layers, and I wrote down why.
3. What did you change, and what did you measure? Say something like: I changed how much dish soap goes in (0 drops, 5 drops, 10 drops, 20 drops) and measured how long the oil and water take to split back into two layers in seconds.
4. What did you keep the same, and why does that matter? Say something like: I kept the same jar with its lid on tight and the same amounts of oil and water the same, so only how much dish soap goes in was different.
5. How many times did you test it? Say something like: 3 times at each of my 4 levels, and I found the middle number.
6. What did you find out? Show me in your numbers. Say something like: Look at my table: 0 drops and 20 drops gave different numbers, and here's the pattern.
7. Was your hypothesis right? How do you know? Say something like: My numbers show whether I was right, partly right or not, and I can show you where.
8. Did anything go wrong, or surprise you? Say something like: One try was odd, so I did it again and wrote it in my logbook.
9. If you did it again, what would you change or test next? Say something like: I'd change a second thing: keep 10 drops of soap and shake 10, 20 and 40 times, and draw a line for how long it stays mixed.