Vogel's Qualitative Analysis
AI-Driven Analytical Learning Suite
An all-in-one platform featuring an AI image analyzer, an interactive step-by-step logic-based guide, and a complete reference library.
Start AnalysisAI Image Analysis
Upload an image of your test result and let the AI identify potential ions.
Interactive Logic-Based Guide
A step-by-step walkthrough of the qualitative analysis process.
Select Analysis Type
Choose which type of ion you would like to analyze step-by-step.
Analysis Log
Detected Ions
No ions detected yet.
Analysis Library
Browse the qualitative analysis schemes for cations and anions based on Vogel's textbook.
Separation Reagent: Dilute HCl
Pb²⁺
Lead(II)
Test: Hot water + K₂CrO₄
Result: Yellow precipitate
Pb²⁺(aq) + CrO₄²⁻(aq) → PbCrO₄(s)
Hg₂²⁺
Mercury(I)
Test: NH₄OH
Result: Black precipitate
Hg₂Cl₂(s) + 2NH₃(aq) → Hg(l) + HgNH₂Cl(s) + NH₄⁺(aq) + Cl⁻(aq)
Ag⁺
Silver(I)
Test: NH₃ → HNO₃
Result: White precipitate dissolves then reforms
AgCl(s) + 2NH₃(aq) → [Ag(NH₃)₂]⁺(aq) + Cl⁻(aq); [Ag(NH₃)₂]⁺(aq) + 2H⁺(aq) → Ag⁺(aq) + 2NH₄⁺(aq)
Separation Reagent: H₂S gas (acidic medium)
Hg²⁺
Mercury(II)
Test: SnCl₂ solution
Result: White → gray precipitate
2Hg²⁺(aq) + Sn²⁺(aq) → Hg₂²⁺(aq); Hg₂²⁺(aq) + Sn²⁺(aq) → 2Hg(l)
Pb²⁺
Lead(II)
Test: K₂CrO₄
Result: Yellow precipitate of PbCrO₄
Pb²⁺(aq) + CrO₄²⁻(aq) → PbCrO₄(s)
Bi³⁺
Bismuth(III)
Test: SnCl₂
Result: Black precipitate
2Bi³⁺(aq) + 3Sn²⁺(aq) → 2Bi(s) + 3Sn⁴⁺(aq)
Cu²⁺
Copper(II)
Test: Excess NH₄OH
Result: Deep blue solution
Cu²⁺(aq) + 4NH₃(aq) → [Cu(NH₃)₄]²⁺(aq)
Cd²⁺
Cadmium(II)
Test: Na₂S
Result: Yellow precipitate
Cd²⁺(aq) + S²⁻(aq) → CdS(s)
As³⁺
Arsenic(III)
Test: (NH₄)₂Sₓ (alkaline polysulfide)
Result: Yellow precipitate dissolves
As₂S₃(s) + 3S²⁻(aq) → 2AsS₃³⁻(aq)
As⁵⁺
Arsenic(V)
Test: (NH₄)₂Sₓ (alkaline polysulfide)
Result: Orange precipitate dissolves
As₂S₅(s) + 3S²⁻(aq) → 2AsS₄³⁻(aq)
Sb³⁺
Antimony(III)
Test: KI
Result: Orange precipitate
Sb³⁺(aq) + 3I⁻(aq) → SbI₃(s)
Sb⁵⁺
Antimony(V)
Test: KI
Result: White precipitate
Sb⁵⁺(aq) + 5I⁻(aq) → SbI₅(s)
Sn²⁺
Tin(II)
Test: NaOH
Result: White precipitates dissolves in excess
Sn²⁺(aq) + 2OH⁻(aq) → Sn(OH)₂(s); Sn(OH)₂(s) + 2OH⁻(aq) → [Sn(OH)₄]²⁻(aq)
Sn⁴⁺
Tin(IV)
Test: Excess NH₄OH
Result: White gelatinous precipitates
Sn⁴⁺(aq) + 4OH⁻(aq) → Sn(OH)₄(s)
Separation Reagent: NH₄OH + NH₄Cl
Fe²⁺
Iron(II)
Test: K₃[Fe(CN)₆]
Result: Dark blue precipitate
3Fe²⁺(aq) + 2[Fe(CN)₆]³⁻(aq) → Fe₃[Fe(CN)₆]₂(s)
Fe³⁺
Iron(III)
Test: KSCN
Result: Blood red solution
Fe³⁺(aq) + SCN⁻(aq) → [Fe(SCN)(H₂O)₅]²⁺(aq)
Al³⁺
Aluminum
Test: Aluminon reagent
Result: Red lake precipitate
Al³⁺(aq) + aluminon → adsorption complex(s)
Cr³⁺
Chromium(III)
Test: NaOH + H₂O₂
Result: Green → yellow solution
2Cr(OH)₃(s) + 3H₂O₂(aq) + 4OH⁻(aq) → 2CrO₄²⁻(aq) + 8H₂O(l)
Zn²⁺
Zinc
Test: Na₂S
Result: White precipitate
Zn²⁺(aq) + S²⁻(aq) → ZnS(s)
Mn²⁺
Manganese(II)
Test: NaBiO₃ + HNO₃
Result: Purple solution
2Mn²⁺(aq) + 5NaBiO₃(s) + 14H⁺(aq) → 2MnO₄⁻(aq) + 5Bi³⁺(aq) + 5Na⁺(aq) + 7H₂O(l)
Ni²⁺
Nickel(II)
Test: Dimethylglyoxime (DMG)
Result: Bright red precipitate
Ni²⁺(aq) + 2DMG(aq) → Ni(DMG)₂(s)
Co²⁺
Cobalt(II)
Test: NH₄SCN + acetone
Result: Blue complex
Co²⁺(aq) + 4SCN⁻(aq) → [Co(SCN)₄]²⁻(aq)
Separation Reagent: (NH₄)₂SO₄ + CH₃COONH₄
Ba²⁺
Barium
Test: K₂CrO₄
Result: Yellow precipitate
Ba²⁺(aq) + CrO₄²⁻(aq) → BaCrO₄(s)
Sr²⁺
Strontium
Test: Flame test
Result: Crimson red flame
Sr²⁺ → characteristic emission(g)
Ca²⁺
Calcium
Test: Ammonium oxalate
Result: White precipitate
Ca²⁺(aq) + C₂O₄²⁻(aq) → CaC₂O₄(s)
Separation Reagent: None required
NH₄⁺
Ammonium
Test: Nessler's reagent
Result: Brown precipitate
2[HgI₄]²⁻(aq) + NH₃(aq) + 3OH⁻(aq) → HgO·Hg(NH₂)I(s) + 7I⁻(aq) + 2H₂O(l)
Na⁺
Sodium
Test: Flame test
Result: Persistent yellow flame
Na⁺ → characteristic emission(g)
K⁺
Potassium
Test: Sodium hexanitritocobaltate(III)
Result: Yellow precipitate
2K⁺(aq) + Na₃[Co(NO₂)₆](aq) → K₂Na[Co(NO₂)₆](s) + 2Na⁺(aq)
Li⁺
Lithium
Test: Flame test
Result: Crimson red flame
Li⁺ → characteristic emission(g)
Mg²⁺
Magnesium
Test: Magneson reagent
Result: Blue precipitate
Mg²⁺(aq) + Magneson → adsorption complex(s)
H⁺
Hydrogen (Proton)
Test: pH paper
Result: Red coloration
H⁺(aq) + Indicator → Color change
How to Use ChemAI
A step-by-step guide to the two powerful analysis modes.
Method 1: AI Image Analysis
- Upload Your Image: Click the upload area or drag and drop a clear photo of your test result.
- Provide Context (Highly Recommended): In the notes field, describe your experiment for better accuracy. For example, "Added dilute HCl to unknown, white precipitate formed."
- Start the Analysis: Click the "Start AI Analysis" button and wait for the results to appear.
- Review Your Report: View the detailed report with possible ions, confidence scores, and conclusions.
Pro Tip:
For the best results, use a well-lit photo with a neutral background to make the reaction results as clear as possible for the AI.
Method 2: Interactive Guide
- Choose an Analysis Type: Scroll to the "Interactive Logic-Based Guide" and click "Cation Analysis" or "Anion Analysis".
- Follow the Steps: The guide will present the first test in the sequence and ask for your observation.
- Provide Your Observation: Click "Yes" or "No" based on your actual or hypothetical lab results.
- Continue the Process: The guide will automatically show the next logical step. Your progress is tracked in the side panels.
Educational Use:
This mode is perfect for pre-lab preparation or for studying the analysis scheme without needing physical materials.
About the Creator
This application was developed by M. Zainur Rifai. As the founder of ChemEdu, Zainur is dedicated to blending education with technology. With a background in chemistry and a focus on educational innovation from Thursina IIBS in Malang, his vision is to create a comprehensive digital ecosystem for chemistry education. ChemEdu is the realization of that vision, built to support students on their learning journey.
M. Zainur Rifai
Founder, ChemEdu
Contact Information
For inquiries or support, please feel free to reach out.