Page 67 - Hybrid PBD 2022 Tg 5 - Kimia

Kimia Tingkatan 5 Bab 4

Keputusan / Result:
Bikar Pemerhatian
Beaker Observation
Lateks menggumpal dengan segera. Pepejal putih terbentuk.
A
The latex coagulated immediately. A white solid was formed.
B Lateks tidak menggumpal.
The latex did not coagulate.

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C Lateks tidak menggumpal.
The latex did not coagulate.
Perbincangan / Discussion:
1. Berdasarkan pemerhatian daripada eksperimen,
Based on the observation from the experiment,
(a) nyatakan satu bahan lain yang menggumpalkan lateks.
state another substance that coagulates latex.

Asid metanoik // Asid hidroklorik
Methanoic acid // Hydrochloric acid
(b) nyatakan satu bahan lain yang mencegah penggumpalan lateks.
state another substance that prevents the coagulation of latex.
Larutan natrium hidroksida // Larutan kalium hidroksida

Sodium hydroxide solution // Potassium hydroxide solution
2. Ramalkan pemerhatian untuk bikar C jika dibiarkan semalaman. Terangkan.
Predict the observation for beaker C if it was left overnight. Explain why.

Lateks menggumpal. Bakteria dari udara menguraikan membran protein dan menghasilkan asid. Ion H
+
meneutralkan cas negatif pada membran protein. Zarah-zarah getah berlanggaran dan memecahkan
membran protein. Molekul-molekul getah terdedah dan menggumpal. / The latex coagulated. Bacteria from

the air broke down the protein membrane forming acids. H ions neutralise the negative charges on the protein membrane. The
+
rubber particles collide breaking the protein membrane. The rubber molecules are exposed and entangle.

Kesimpulan / Conclusion:
1. Penambahan asid ke dalam lateks menggumpalkan lateks.

The addition of acid to latex causes latex to coagulate.
2. Penambahan alkali ke dalam lateks mencegah penggumpalan lateks.

The addition of alkali to latex prevents the coagulation of latex.

8. Terangkan makna pemvulkanan getah. SP 4.2.3 TP1
Explain the meaning of rubber vulcanisation.
Pemvulkanan ialah proses penghasilan getah yang lebih kenyal dan berkualiti dengan mewujudkan rangkai

silang sulfur di antara rantai polimer getah. / Vulcanisation is a process of producing rubber that is more elastic and with better
qualities by introducing sulphur cross-links between rubber polymer chains.

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04 Hybrid Kimia Tg5.indd 138 05/11/2021 4:20 PM