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English reading
Textiles
380. Mitä ero luonnonkuiduilla ja tekokuidilla/ what is the difference between natural fibers and man-made fibers?
381. määrittele käsite ja anna yksi esimerkki /define the concept and give one example
kasvikuitu/ vegetable fiber
eläinkuitu/ animal fiber
muuntokuitu/ modified fiber
synteetinen kuittu/ synthetic fiber
382. Mistä valmistetaan/ What is the following made of:
villa/ wool
cotton/ puuvilla
silkki/ silk
383. kirjoita seuraavia sanoja käyttämällä tekstiilikituihin liittyviä lauseita: luonnonkuitu, kasvikuitu, proteiinikuitu, eläinkuitu. tekokuitu, pellava. villa, viskoosi, selluloosakuitu/ write the following words using phrases related to textile fibers: natural fiber, vegetable fiber, protein fiber, animal fiber. man-made fiber, linen. wool, viscose, cellulose fiber
384.
Miten kuluttaja voi omilla valinnoillaan ottaa huomioon tuotteen ympäristövaikutukset, kun hän hankkii uusia vaatteita. Kirjoita viisi ohjetta/ How can the consumer, in his choices, take into account the environmental impact of the product when he acquires new clothes. Write five instructions.
387. Kuvassa on osa polyesterin rakennekaavaa/ The picture in the book on page 259 shows part of the structural formula of polyester.
a) Mitä alkuaineita polyesterissä on/ What are the elements in polyester?
b) Mitä tarkoittavat polyesteri-nimen alkuosa poly ja loppuosa esteri/ What is meant by the first part of the name polyester poly and the rest of the ester?
c) Ota selvää, miten polyesteriä valmistetaan/ Find out how polyester is made.
SOAP!
Soap preparation has been going on for 4500 years. Why is soap preparation one of humanity's most important inventions?
Saponification reaction.
How soap works
To clean things with water we need to
wet and soak the fibres of the cloth
separate the grease, dirt and dust from the fibres
suspend the grease in water, so it can be washed away
Soap molecules have a hydrophobic (water hating) hydrocarbon chain and a hydrophilic (water loving) ionic charged head that lets the molecules dissolve in water. The molecules interact with both water and grease which is largely organic. The hydrophobic hydrocarbon chain tails are attracted to the grease and become embedded in it. When the water is agitated the grease is released from the cloth fibre and is surrounded by soap molecules. Rinsing then removes these droplets.
399. Mitä pesuaineita olet käyttänyt viimeisen viikon aikana/ What detergents have you used during the last 5 days?
400.
a. mitä tensidit ovat? What are tensides/surfactants?
b. Millainen rakenne tensideillä on? What kind of structure do surfactants have? Draw out the chemical structure.
401. Mihin tensidin vaikutus perustuu? What is the chemical effect of surfactants? Draw a diagram of how soaps work.
402. Mitkä tekijät vaikuttavat pyykin pesuun tensidin lisäksi? In addition to surfactants which other factors affect laundry washing?
403. Miten saippuaa valmistetaan? How is soap prepared? write the chemical equation and name the molecules involved.
Making soap lab
…………………………………………………………………………………………………………………………………………………….
Equipment
- 100 ml measuring cylinder
- 250 ml beaker
- stirring rod
- Bunsen burner
- weighing balance
- thermometer
Substances
- coconut oil
- 30% NaOH solution (sodium hydroxide)
CORROSIVE
- colourings
- essential oils
Safety
- goggles and gloves to be worn at all times
- NaOH is corrosive
- lab coat
METHOD
Weigh out 50g of coconut butter (kookosrasva) into the beaker.
Place the beaker on the heat and, when the coconut butter starts to liquidify, use a thermometer.
Gently heat the mixture on a low flame.
Note: Temperature in fat solutions rises much more rapidly than when you boil water so watch out!
Make sure the temperature does not go above 60 °C.
When the temperature is 40 - 50 °C, your teacher will carefully add 28 ml of alkaline solution (sodium hydroxide) into the mixture.
At this point you can turn off the flame. Switch the flame back on if the temperature goes below 40 °C.
Mix gently with the stirring rod.
At this point you can measure the pH using pH paper and observe how the pH changes as the reaction progresses.
When the solution begins to thicken, the saponification (soap production) has begun. Continue to mix for at least 20 minutes for all of the alkaline to react with the fatty acids.
Once the mixture has turned into thin “porridge”, you can add colourings and/or essential oils. - Only use a small pinch of colourings even if the colour does not change much. The colour may change further when your soap solidifies. Only add a few drops of essential oils.
Pour the soap into a mould to solidify. Cover with cling film/foil and leave at least until the next day. The saponification reaction will continue after the soap has been taken off the heat. You should allow the soap to sit for a few days before using it.
Before using the soap, measure its alkalinity with pH paper by dissolving some soap into a small amount of water. If the pH is below 10, you can use the soap to wash your hands. If it feels pleasant in your hands, you can use it to wash your entire body.
POST-LAB DISCUSSION
Which substances does soap contain?
Why did the solution’s pH rise when you were heating it?
What is soap’s cleaning power based on?
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