Pelangi Indikator pH

Memetakan perubahan warna indikator di seluruh rentang pH penuh

Qualitative Analysis Beginner (Middle School) 45 menit ~$8,00

Tujuan

Amati bagaimana berbagai indikator pH berubah warna pada nilai pH tertentu dan pahami konsep rentang transisi indikator.

Latar Belakang

pH indicators are weak acids or bases whose conjugate forms have different colors. Each indicator has a characteristic transition range where it changes color. By testing multiple indicators across a range of buffered solutions, students create a visual map of indicator behavior that reinforces concepts of acid-base equilibrium and the Henderson-Hasselbalch equation.

Peringatan Keselamatan

  • Indicators can stain skin and clothing
  • Extreme pH solutions (pH 1, 14) are corrosive
  • Avoid mixing different buffer solutions

APD yang Diperlukan

goggles lab_coat

Bahan

  • Buffer solutions (pH 1–14) (5 mL each)
    Pre-prepared set
  • Methyl orange indicator (5 mL)
    pH 3.1–4.4 range
  • Bromothymol blue indicator (5 mL)
    pH 6.0–7.6 range
  • Phenolphthalein indicator (5 mL)
    pH 8.2–10.0 range
  • Universal indicator (5 mL)
    Full pH range
  • Litmus solution (red and blue) (5 mL each)
    Simple acid/base test

Peralatan

Spot plate or microwell plate Dropper pipettes (one per indicator) pH meter or pH paper White background paper

Prosedur

1

Arrange the spot plate and add 10 drops of each buffer solution (pH 1 through 14) across each row.

10 menit Handle pH 1 and 14 solutions carefully
2

Add 2 drops of methyl orange to the first row of buffer solutions. Record the color at each pH.

5 menit
3

Add 2 drops of bromothymol blue to the second row. Record the color at each pH.

5 menit
4

Add 2 drops of phenolphthalein to the third row. Record the color at each pH.

5 menit
5

Add 2 drops of universal indicator to the fourth row. Observe the full rainbow of colors.

5 menit
6

Create a color chart recording each indicator's color at every pH level. Identify each indicator's transition range.

15 menit

Hasil yang Diharapkan

Methyl orange: red (acidic) to yellow (basic) around pH 3–4. Bromothymol blue: yellow to blue around pH 6–7.6. Phenolphthalein: colorless to pink around pH 8–10. Universal indicator: red through violet across the full pH range.

Pembersihan

Pour solutions into the appropriate waste container (acid or base). Rinse spot plates thoroughly with distilled water.

Detail

Kategori
Qualitative Analysis
Tingkat Kesulitan
Beginner (Middle School)
Durasi
45 menit
Perkiraan Biaya
$8,00
Langkah
6
Bahan
6

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Frequently Asked Questions

What is the objective of Pelangi Indikator pH?
Amati bagaimana berbagai indikator pH berubah warna pada nilai pH tertentu dan pahami konsep rentang transisi indikator.
How difficult is Pelangi Indikator pH?
This experiment is rated as Beginner (Middle School). It takes approximately 45 minutes to complete.
What safety precautions are needed for Pelangi Indikator pH?
Key safety precautions include: Indicators can stain skin and clothing; Extreme pH solutions (pH 1, 14) are corrosive; Avoid mixing different buffer solutions.
What materials are needed for Pelangi Indikator pH?
The main materials required are: Buffer solutions (pH 1–14), Methyl orange indicator, Bromothymol blue indicator, Phenolphthalein indicator, Universal indicator.
What results should I expect from Pelangi Indikator pH?
Methyl orange: red (acidic) to yellow (basic) around pH 3–4. Bromothymol blue: yellow to blue around pH 6–7.6. Phenolphthalein: colorless to pink around pH 8–10. Universal indicator: red through violet across the full pH range.