// Field files for grades 5–12Observe. Measure. Explain.
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Paper towel absorbency lab

Why some paper towel brands soak up more water than others
ChemistryGrades 4–825–30 minHazard lowNGSS MS-PS1-1 — structure and properties of matterNGSS SEP 4 — analyze and interpret data

01 // Question

How does the brand of paper towel change how much water it can absorb before dripping?

A testable question names one thing you change (brand) and one thing you measure (water absorbed).

02 // Variables

Independent

Paper towel brand
  • Brand A
  • Brand B
  • Brand C

Dependent

Volume of water absorbed before dripping
  • Milliliters absorbed
  • Number of drops absorbed before a drip forms
Controlledsame size sheet of paper towel · same method of adding water (drop by drop) · same starting dry mass, if weighing · same surface underneath

03 // Hypothesis

IF a thicker, more textured paper towel brand is tested, THEN it will absorb more water before it starts to drip, BECAUSE a thicker towel has more fiber material and more small gaps between fibers to hold water through capillary action.

04 // Procedure

1. Set up each brand

Cut an equal-size sheet from each paper towel brand and lay it flat over a bowl or tray.

2. Fill a dropper

Fill a dropper or graduated cylinder with a measured amount of water.

3. Add water slowly

Add water to the center of the sheet one drop or milliliter at a time, pausing between additions.

4. Watch for dripping

Stop as soon as water starts dripping through the paper towel onto the surface below.

5. Record the total

Record the total amount of water added before dripping began, and repeat for each brand.

05 // Data table

Paper towel brandWater absorbed before drip (mL)Trial 2 (mL)Average (mL)
Brand A____________
Brand B____________
Brand C____________

06 // What to expect

A thicker paper towel with more visible texture usually absorbs more water before dripping, because it has more total fiber material and more of the small gaps between fibers that pull water in and hold it through capillary action.

A thinner, smoother paper towel often absorbs less total water but may absorb it faster at first, since water can travel across a smoother, less dense sheet of fibers more quickly, even though the sheet holds less overall.

07 // Lab notes

  • Add water slowly and steadily — pouring too fast can make a towel drip early even if it could have absorbed more given time.
  • Cut every brand's test sheet to the exact same size, since a bigger sheet naturally holds more water regardless of the brand.
  • Work over a tray or in a sink, since this lab is intentionally messy by design.

08 // Remember

A thicker towel isn't automatically the fastest. It's usually the one that holds the most before it finally gives up and drips.

09 // Questions people ask

Why do some paper towel brands absorb more water than others?

Absorbency depends on how the paper towel's fibers are structured — how thick the sheet is, how tightly or loosely the fibers are woven, and how many small gaps exist between them for water to be pulled into through capillary action. Brands engineered with a thicker, more open fiber structure generally hold more water.

What is the independent variable in a paper towel absorbency experiment?

The paper towel brand being tested is the independent variable — the thing intentionally changed between trials. The dependent variable is typically the volume of water the sheet absorbs before it starts to drip.

Why does the water need to be added slowly instead of poured all at once?

Pouring water quickly can overwhelm a paper towel's absorption rate and cause it to drip early, even if it could have held more water given more time. Adding it slowly, drop by drop, gives a more accurate measurement of the towel's true absorbent capacity rather than its absorption speed.

10 // Keep going

Printable · student data sheet + answer key
PDF · letter size · black and white friendly · coming soon
PDF in progress