praktikum kimia "makromolekul" uji karbohidrat dan protein || Suci Novitasari || XII MIPA 2

Summary

In this chemistry practical, Novita Sari, a student from class 12 MIPA 2, demonstrates tests for carbohydrates and proteins in various food items. The first part focuses on testing for carbohydrates using iodine solution, revealing that bread, rice, and potatoes contain carbohydrates, while milk powder, eggs, and sugar do not. The second part tests for protein content in foods like soy sauce, oil, milk, and egg whites. The results show that soy sauce, milk, and egg whites contain proteins, while oil does not. The video concludes with an informative and engaging presentation of the experiment results.

Takeaways

• 😀 The speaker introduces themselves as Cici Novita Sari from class 12 MIPA 2, who is conducting a chemistry practical experiment on macromolecules.
• 😀 The experiment involves testing various foods (roti, nasi, telur, susu bubuk, kentang, and gula) with Lugol's solution to check for the presence of carbohydrates.
• 😀 When Lugol's solution is added to foods containing carbohydrates (roti, nasi, kentang), it turns blue or black.
• 😀 Foods like telur (egg), susu bubuk (powdered milk), and gula (sugar) do not change color, indicating no presence of carbohydrates.
• 😀 After the carbohydrate test, the speaker proceeds to test for proteins in four different food items: kecap (soy sauce), minyak (oil), susu cair (liquid milk), and putih telur (egg white).
• 😀 The protein test involves heating the samples in hot water and adding a few drops of vinegar to check for clumping or coagulation.
• 😀 The kecap (soy sauce) forms clumps, indicating the presence of protein.
• 😀 The minyak (oil) does not form clumps, indicating it does not contain protein.
• 😀 The susu cair (liquid milk) forms clumps, indicating the presence of protein.
• 😀 The putih telur (egg white) also forms clumps, confirming the presence of protein in it.

Q & A

What is the main objective of the practical experiment in the script?

The main objective of the practical experiment is to test the presence of carbohydrates and proteins in various food items using specific reagents like Lugol’s solution and vinegar.

Which food items were tested for carbohydrates in the experiment?

The food items tested for carbohydrates were powdered milk, bread, rice, and boiled egg.

What reagent was used to test for carbohydrates in the food items?

Lugol’s solution (also referred to as Betadine) was used to test for carbohydrates.

What result indicates the presence of carbohydrates when using Lugol’s solution?

A blue-black color change indicates the presence of carbohydrates when using Lugol’s solution.

Which food items tested positive for carbohydrates in the experiment?

Bread and rice tested positive for carbohydrates, as evidenced by the blue-black color change of the Lugol’s solution.

Which food items tested negative for carbohydrates in the experiment?

Boiled egg and powdered milk tested negative for carbohydrates, as the Lugol’s solution remained unchanged.

Which materials were tested for proteins in the second part of the experiment?

The materials tested for proteins were soy sauce, cooking oil, liquid milk, and egg white.

How was protein presence tested in the materials during the experiment?

Protein presence was tested by adding vinegar to the materials after placing them in hot water. The formation of clumps or gumps indicated the presence of protein.

Which substances tested positive for proteins in the experiment?

Soy sauce, liquid milk, and egg white tested positive for proteins, as they formed clumps after the addition of vinegar.

Which substance tested negative for protein in the experiment?

Cooking oil tested negative for proteins, as no clumps formed after the addition of vinegar.