LEMAK DAN GETAH

Natural rubber also known as / Getah asli juga dikenali sebagai...

• Polyisoprene / Poliisoprena

• Poly-2-methylbutene / Poli-2-metilbutena

• Polysacharide / Polisakarida

• Polypeptide / Polipeptida

Which of the following is true? Yang manakah di antara berikut adalah benar?

• Vulcanised rubber is softer than unvulcanised rubber / Getah tervulkan lebih lembut daripada getah tak tervulkan

• Unvulcanised rubber is less elastic than vulcanised rubber / Getah tak tervulkan kurang kenyal daripada getah tervulkan

• Unvulcanised rubber is stronger than vulcanised rubber / Getah tak tervulkan lebih kuat daripada getah tervulkan

Vulcanisation is

Pemvulkanan ialah

• A process whereby a substance in aqueous solution is decomposed into its constituent elements.

  Proses di mana bahan dalam keadaan larutan akueus diuraikan kepada unsur juzuknya.

• A reaction between an acid and an alkali to produce salt and water.

  Tindak balas di antara asid dan alkali untuk menghasilkan garam dan air.

• A process of adding sulphur to natural rubber molecules.

  Proses penambahan sulfur kepada molekul-molekul getaj asli

• A process of converting liquid fat into solid fat.

  Proses penukaran lemak cecair kepada lemak pepejal.

Which of the following is not the uses of natural rubber?

Yang manakah bukan kegunaan getah asli?

• To produce rain coat

  Membuat baju hujan

• To produce tyre

  Membuat tayar

• To produce rubber band

  Membuat gelang getah

• To produce gloves

  Membuat sarung tangan

Which of the following is not a reason for vulcanisation?

Yang manakah bukan sebab untuk pemvulkanan?

• To improve the elasticity of rubber

  Menambah kekenyalan getah

• To improve the strength of rubber

  Menambah kekuatan getah

• To improve the hardness of rubber

  Menambah kekerasan getah

• To produce a rubber that is easily oxidised

  Menghasilkan getah yang mudah dioksidakan

When sulphur is added,

Apabila sulfur ditambah,

• The rubber becomes softer

  Getah menjadi lembut

• The rubber becomes less elastic

  Getah menjadi kurang elastik

• The rubber becomes less resistant to heat

  Getah menjadi kurang tahan terhadap haba

• The rubber cannot oxidised easily

  Getah tidak mudah teroksida

The following substances can prevent latex from coagulates, except

Bahan berikut boleh menghalang lateks daripada menggumpal, kecuali

• Vinegar

  Cuka

• Dilute sodium hydroxide solution

  Larutan natrium hidroksida cair

• Ammonia solution

  Larutan ammonia

What is the function of sulphur in vulcanised rubber?

• Rubber can return to its original shape after being stretched

  Getah boleh kembali ke rupa asal selepas diregang

• Rubber becomes longer than its original shape after being stretched

  Getah menjadi lebih panjang daripada asal selepas diregang

• Rubber can be melts easily when exposed to heat

  Getah mudah untuk cair apabila terdedah kepada haba

Which substance is used to prevent coagulation of lates?

Bahan manakah yang boleh diguna untuk menghalang penggumpalan lateks?

• Ethanoic acid

  Asid etanoik

• Methanoic acid

  Asid metanoik

• Ethyl ethanoate

  Etil etanoat

• Ammonia solution

  Larutan ammonia

How hydrochloric acid can cause coagulation of latex?

• Hydroxide ion neutralised the negatively-charge protein membrane of rubber particles.

  Ion hidroksida meneutralkan membran protein getah yang bercas negatif

• Hydrogen ion neutralised the negatively-charge protein membrane of rubber particles.

  Ion hidrogen meneutralkan membran protein getah yang bercas negatif

• Hydrogen ion neutralised the positively-charge protein membrane of rubber particles.

  Ion hidrogen meneutralkan membran protein getah yang bercas positif