Why are GORE-TEX type materials are waterproof and yet breathable?
The material is made up from nylon laminated with a PTFE / polyurethane membrane. The membrane is too fragile on its own hence why it is combined with the nylon. The holes in membrane are too small for water to pass through but are big enough for water vapour to pass through.
LB
Related Chemistry GCSE answers
All answers ▸Calculate the atom economy of the following equation, assuming that KNO3 is the desired product. KOH + HNO3 ---> KNO3 + H2O (Mr of reactants and products, KOH - 56.1, HNO3 - 63.0, KNO3 - 101.1, H2O - 18.0)
Describe the bonding present in a piece of sodium metal.
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Describe the general structure of an atom.