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 ▸Describe the bonding in i)NaCl, ii) HCl, iii) Mg
0.0960g of Magnesium was reacted with 25cm^3 of HCL of 0.4mol/dm^3 concentration. Calculate the moles of each one and determine which one is in excess
A student titrated a solution of 25 cm3 of NaOH of concentration 0.1 mol/dm3 with H2SO4. She achieved four results; 25.8 cm3, 26.15 cm3, 26.25 cm3 and 26.45 cm3. Calculate the concentration of H2SO4 using concordant titres.
A student carries out an experiment to determine the melting point of a waxy solid. She heats a sample until it melts, then measures and records its temperature as it cools down. Explain how the student could use her results to decide whether the waxy