CHAPTER 6 ABSORPTION

Which Type of Materials Can Absorb Water?

Some materials can absorb water while some cannot. The materials that can absorb water are called "absorbent materials" and the one that cannot absorb water are called "non-absorbent materials".

Absorbent materials are:

• textile products that are made of cloth (cotton, silk, wool) for examples towels, handkerchiefs, t-shirts, undergarments, socks, jeans, denim, robes, traditional cloth diapers, shirts, ties, blouses, formal dresses, lingerie, pyjamas, kimonos, blankets, carpets, woolen garments and etc.
• objects that are made of cotton for examples cotton bud, coffee filters, cotton wool, face cotton, floor mop, thread and etc.
• objects that are made of wood for examples envelopes, toilet roll, books, tissue paper, newspaper and etc. Coconut-husk and tree trunk also can absorb water.
• other objects such as sponges (natural and synthetic) and feathers.

Example of absorbent material: 

Tissue paper

Non-absorbent materials are:

• objects that are made of metal for examples key, nail clipper, coin, tin can and etc.
• objects that are made of rubber for examples eraser, rubber gloves, tyre and etc.
• objects that are made of plastic for examples plastic pail, plastic bag, cutting board, rain coat, umbrella, tent, polystyrene container and etc.
• objects that are made of glass
• other objects such as pebbles, stones and marbles.

Example of Non-absorbent material:

Absorption Ability Are Differ from Materials to Materials

Different materials have a different ability to absorb water. Some materials can absorb more water than others. For example, a sponge can absorb more water than a roll of newspaper.

Experiment on Sponges

The ability to absorb water can also be differ from sponges to sponges and the following circumstances are taking into account.

• material - man-made sponges commonly made from cellulose wood fibres or foamed plastic polymers
• size - a large sponge can hold more water than a small sponge
• condition - a dry sponge can hold more water than a wet sponge because the wet sponge is closer to saturation and as such cannot hold more water. Sponges with more tiny holes can absorb more water than the sponges with less tiny holes
• fluid - the type of fluid being absorbed, water or water-based solutions