Activity 4E:
1. Carry out the activity as a group discussion.
2. Present the answers for the following questions using an i-Think map.
(a) Classify the following substance into coagulant and anti-coagulant for latex.
(b) Explain why latex that coagulates naturally takes a longer time compared to when a coagulant is added.
(c) Using a diagram, describe the mechanisms that prevent latex from coagulating.
Answer:
(a)
Coagulant: Formic acid, formaldehyde, vinegar.
Anticoagulant: Ammonia solution, sodium hydroxide solution.
(b)
Natural coagulation process is due to the secretion of lactic acid by bacteria. Lactic acid is secreted in a very small quantity and causes coagulation to take place very slowly.
(c)
Diagram and description.
1. Carry out the activity as a group discussion.
2. Present the answers for the following questions using an i-Think map.
(a) Classify the following substance into coagulant and anti-coagulant for latex.
(b) Explain why latex that coagulates naturally takes a longer time compared to when a coagulant is added.
(c) Using a diagram, describe the mechanisms that prevent latex from coagulating.
Answer:
(a)
Coagulant: Formic acid, formaldehyde, vinegar.
Anticoagulant: Ammonia solution, sodium hydroxide solution.
(b)
Natural coagulation process is due to the secretion of lactic acid by bacteria. Lactic acid is secreted in a very small quantity and causes coagulation to take place very slowly.
(c)
Diagram and description.
