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<html lang="en">
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    <span class="token c-coeff" data-target="coeff" title="Coefficient">2</span>
    <span class="token c-plain">Al</span><span class="token c-sub1 sub" data-target="sub1" title="Subscript">2</span><span class="token c-plain">(SO</span><span class="token c-plain sub">4</span><span class="token c-plain">)</span><span class="token c-sub2 sub" data-target="sub2" title="Polyatomic Subscript">3</span>
    <span style="width: 6px;"></span>
    <span class="token c-state" data-target="state" title="State Symbol">(aq)</span>
  </div>

  
  <div class="badges-grid">
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      <div class="badge-title"><span>●</span> Coefficient</div>
      <div class="badge-desc">Multiplies whole formula (2 units)</div>
    </div>
    <div class="badge-card card-sub1" data-target="sub1">
      <div class="badge-title"><span>●</span> Subscript</div>
      <div class="badge-desc">2 Al atoms per unit</div>
    </div>
    <div class="badge-card card-sub2" data-target="sub2">
      <div class="badge-title"><span>●</span> Group Subscript</div>
      <div class="badge-desc">Multiplies (SO₄) by 3</div>
    </div>
    <div class="badge-card card-state" data-target="state">
      <div class="badge-title"><span>●</span> State Symbol</div>
      <div class="badge-desc">Aqueous (dissolved in water)</div>
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    <div class="calc-header">Total Atom Count (2 Formula Units)</div>
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        <div class="atom-math">2 × 2</div>
        <div class="atom-total">4 Al</div>
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      <div class="atom-pill" id="pill-s">
        <div class="atom-symbol">Sulfur</div>
        <div class="atom-math">2 × (1 × 3)</div>
        <div class="atom-total">6 S</div>
      </div>
      <div class="atom-pill" id="pill-o">
        <div class="atom-symbol">Oxygen</div>
        <div class="atom-math">2 × (4 × 3)</div>
        <div class="atom-total">24 O</div>
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Writing and Balancing Chemical Equations for Mass Conservation

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
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      max-width: 80px;
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    .atom-C { background: #334155; }
    .atom-H { background: #0284c7; }
    .atom-O { background: #ea580c; }

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</head>
<body>

  
  <div class="controls">
    <button class="step-btn active" onclick="setStep(0)">1. Unbalanced</button>
    <button class="step-btn" onclick="setStep(1)">2. Fix C &amp; H</button>
    <button class="step-btn" onclick="setStep(2)">3. Fix O</button>
    <button class="play-btn" id="playBtn" onclick="togglePlay()" title="Toggle Auto-play">⏸</button>
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  </div>

  
  <div class="balance-grid">
    <div class="grid-header">
      <span>Reactants</span>
      <span>Atom</span>
      <span>Products</span>
    </div>

    
    <div class="element-row" id="row-C">
      <div class="count-box left">
        <div class="dots" id="dots-left-C"></div>
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      <div class="count-box left">
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        <span class="count-val" id="val-left-O">2</span>
      </div>
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      <div class="count-box right">
        <span class="count-val" id="val-right-O">3</span>
        <div class="dots" id="dots-right-O"></div>
      </div>
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  </div>

  
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      document.getElementById('eqBox').innerHTML = data.eqHtml;

      // Update Rows
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        document.getElementById(`val-left-${elem}`).textContent = leftCount;
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      color: #1e293b;
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      align-items: center;
      justify-content: center;
      min-height: 100%;
      padding: 12px 8px;
      user-select: none;
    }

    .comparison-grid {
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      grid-template-columns: 1fr auto 1fr;
      width: 100%;
      max-width: 620px;
      align-items: stretch;
      gap: 4px;
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      display: flex;
      flex-direction: column;
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      text-align: center;
      padding: 8px 6px;
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      <div class="badge badge-safe">✓ Change Coefficient</div>
      <div class="formula-box">
        <span class="highlight-coeff">2</span><span>H</span><sub>2</sub><span>O</span>
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      <div class="desc desc-safe">2 separate water molecules</div>
      <div class="desc-detail">Safe to drink (Water)</div>
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      <div class="vs-pill">vs</div>
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      <div class="badge badge-danger">🚫 DO NOT CHANGE</div>
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        <span>H</span><sub>2</sub><span>O</span><span class="highlight-sub">2</span>
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      <div class="desc-detail">Toxic bleach / disinfectant</div>
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    <span class="accent-red">Subscripts</span> define <strong>WHAT</strong> it is. <span class="accent-green">Coefficients</span> count <strong>HOW MANY</strong>.
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      <span>⚖️ Law of Conservation of Mass</span>
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      Reactants (<span class="tag-c">1 C</span> + <span class="tag-h">4 H</span> + <span class="tag-o">4 O</span>) = Products (<span class="tag-c">1 C</span> + <span class="tag-h">4 H</span> + <span class="tag-o">4 O</span>) &nbsp;|&nbsp; <span class="tag-mass">150.0 g = 150.0 g</span>
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Relationship Between Mole, Atomic Mass and Molecular Mass

Relative Atomic Mass and Relative Isotopic Mass Definitions

Calculating Empirical Formulae from Composition Data

Determining Molecular Formulae from Empirical Formula and Mr

Writing and Balancing Full Chemical Equations

Constructing Ionic Equations and Identifying Spectator Ions

Reacting Mass Calculations and Limiting Reagents

Molar Gas Volume and Ideal Gas Equation Calculations

Calculating Percentage Yield in Chemical Syntheses

Calculating and Evaluating Atom Economy

science

Amount of Substance and Stoichiometry

Classifying Synthesis, Decomposition, and Combustion Reactions

Single and Double Replacement Reactions and Activity Series

Predicting Solubility and Precipitate Formation in Double Replacement Reactions

Writing Complete Ionic Equations and Identifying Spectator Ions

Constructing Net Ionic Equations for Insoluble Precipitates

Net Ionic Equations for Acid-Base Neutralization Reactions

Balancing Redox Equations Using Oxidation Number Changes

Chemical Reactions, Equation Balancing, and Net Ionic Equations

Atoms, Chemical Elements, and Universal Symbols

Formulae of Diatomic and Polyatomic Elements

Writing Chemical Formulae of Simple Compounds

Deducing Chemical Formulae for First 20 Elements and Common Compounds

Naming and Formulae of Simple Covalent Molecules

Deducing Formulae with Transition Metal Oxidation States

Counting Atoms in Formulae Containing Brackets

GCSE Exam Mastery: Chemical Formulae Deduction

Chemical Symbols and Formulae

Conservation of Mass in Chemical Reactions

Conservation of Mass in Open and Closed Systems

Explaining Mass Loss in Gas-Evolving Reactions

Explaining Mass Gain in Metal Oxidation Reactions

Particle Models for Conservation of Mass in Open Flasks

Exam Mastery: Mass Conservation and Open-System Experiments

Conservation of Mass and Non-Enclosed Systems

Metody otrzymywania kwasów beztlenowych i tlenowych

Otrzymywanie wodorotlenków rozpuszczalnych w wodzie

Otrzymywanie wodorotlenków trudno rozpuszczalnych metodą strąceniową

Doświadczenie: strącanie osadów soli i wodorotlenków nierozpuszczalnych

Synteza kwasów beztlenowych z pierwiastków

Otrzymywanie kwasów tlenowych z bezwodników kwasowych

Otrzymywanie kwasów i soli metodą wypierania ze związków

Doświadczenie: otrzymywanie soli w reakcji metalu z kwasem oraz tlenku z kwasem

Otrzymywanie soli w reakcjach tlenków z kwasami i zasadami

Projektowanie wieloetapowych schematów otrzymywania soli

Metody otrzymywania wodorotlenków, kwasów i soli

Distinguishing Empirical and Molecular Formulae

Empirical Formulae from Molecular and Lattice Models

Empirical Formulae from 2D Particle Diagrams

Determining Empirical Formula from Reacting Masses

Investigating Empirical Formula: Magnesium Oxide Crucible Practical

Converting Empirical Formula to Molecular Formula Using Relative Molecular Mass

GCSE Exam Mastery: Empirical Formula Calculations and Models

Empirical Formulae and Molecular Structures

Estabilidad nuclear y fuerza nuclear fuerte

Tipos de radiactividad: emisiones alfa, beta y gamma

Vida media y datación radiométrica

Fisión nuclear y reacciones en cadena

Fusión nuclear y energía estelar

Energía nuclear: fisión, fusión y gestión de residuos

Aplicaciones médicas e industriales de los radioisótopos

Radiactividad y energía nuclear

Relative Atomic Masses of Common Elements: Reference and Practice

Calculating Relative Molecular Mass from Chemical Formulae

Calculating Relative Formula Mass with Brackets and Hydrated Salts

Practice: Calculating Relative Masses of Various Compounds

Calculating Percentage by Mass of an Element in a Compound

Interpreting Balanced Equations Quantitatively

Verifying Mass Conservation Using Total Mr of Reactants and Products

Exam Mastery: Relative Formula Mass and Stoichiometry

Relative Formula Mass and Quantitative Equations

Klasyfikacja wodorotlenków — zasady a wodorotlenki nierozpuszczalne

Klasyfikacja wodorotlenków ze względu na charakter chemiczny

Zasadowy odczyn roztworów wodorotlenków metali grup 1 i 2

Doświadczenie: badanie właściwości amfoterycznych wodorotlenku cynku Zn(OH)2

Doświadczenie: badanie właściwości amfoterycznych wodorotlenku glinu Al(OH)3

Tworzenie hydroksokompleksów glinu i cynku

Amfoteryczność wodorotlenków chromu(III), ołowiu(II) i berylu

Porównanie zachowania soli metali amfoterycznych i nieamfoterycznych wobec zasad

Wnioskowanie o charakterze chemicznym wodorotlenku z wyników badań

Trwałość termiczna i rozkład wodorotlenków trudno rozpuszczalnych

Wodorotlenki — charakter chemiczny, amfoteryczność i hydroksokompleksy

The Law of Conservation of Mass in Closed and Open Systems

Writing Chemical Equations from Word Equations

Balancing Synthesis and Decomposition Equations

Writing Balanced Chemical Equations for Main Group Reactions

Balancing Complete and Incomplete Combustion Equations

Balancing Equations Involving Unchanged Polyatomic Groups

Interpreting Stoichiometric Molar Ratios in Balanced Equations

GCSE Exam Mastery: Balancing Complex Chemical Equations

Balancing Chemical Equations and Mass Conservation

Group 0 Noble Gases: Properties and Unreactivity

Group 1 Alkali Metals: Properties and Water Reactions

Explaining Reactivity Trends in Group 1 Metals

Group 7 Halogens: Properties and Displacement Reactions

Explaining Reactivity Trends in Group 7 Halogens

Predicting Properties and Reactivity Across the Periodic Table

Periodic Groups and Chemical Trends

Zapis reakcji zobojętniania: mocny kwas + mocna zasada w formie jonowej

Zobojętnianie z udziałem słabych kwasów i wodorotlenków nierozpuszczalnych

Tabela rozpuszczalności i zapis jonowy reakcji strąceniowych soli

Strącanie osadów w układach sól + sól oraz sól + zasada

Reakcje wybranych soli z wodą — zapis jonowy procesów hydrolizy

Równania reakcji jonowych — zobojętnianie, strącanie i hydroliza

Organización de la tabla periódica actual

Clasificación de elementos: metales, no metales y metaloides

Carga nuclear efectiva y efecto pantalla

Tendencias periódicas: radio atómico e iónico

Energía de ionización y afinidad electrónica

Electronegatividad y carácter metálico

Estados de oxidación y reactividad por grupos

Elementos de transición y tierras raras

Resolución de problemas con propiedades periódicas

Tabla periódica y propiedades periódicas

Doświadczenie: badanie reakcji tlenków zasadowych z wodą i kwasami

Równania reakcji tlenków zasadowych z kwasami — zapis cząsteczkowy i jonowy

Doświadczenie: badanie reakcji tlenków kwasowych z wodą i zasadami

Reakcje tlenków kwasowych nierozpuszczalnych w wodzie (SiO2) z zasadami

Doświadczenie: badanie amfoterycznego charakteru tlenku glinu Al2O3

Reakcje Al2O3 z kwasami i zasadami — tworzenie tetrahydroksoglinianów

Amfoteryczny charakter tlenku berylu BeO i tlenku cynku ZnO

Reakcje między tlenkami zasadowymi a kwasowymi — synteza soli tlenowych

Wnioskowanie o charakterze chemicznym tlenku na podstawie obserwacji laboratoryjnych

Ciągi przemian chemicznych tlenków w zadaniach analitycznych

Tlenki kwasowe, zasadowe, amfoteryczne i obojętne — doświadczenia i reakcje

Reakcje kwasów nieorganicznych z metalami aktywnymi

Doświadczenie: badanie reaktywności metali względem kwasów i wody

Stechiometria reakcji roztwarzania metali w kwasach nieutleniających

Reakcje kwasów z tlenkami metali

Wypieranie słabszych i lotniejszych kwasów z ich soli

Reakcje strącania osadu soli w reakcji sól + kwas

Zastosowanie reakcji soli z kwasami w usuwaniu kamienia i trawieniu metali

Projektowanie doświadczeń badających właściwości chemiczne kwasów

Właściwości chemiczne kwasów i reakcje wypierania

Klasyfikacja i budowa wodorków metali oraz niemetali

Wodorki jonowe metali grup 1 i 2 — NaH, CaH2 i ujemny stopień utlenienia wodoru

Reakcje wodorków jonowych z wodą — powstawanie zasad i wydzielanie wodoru

Wodorki kowalencyjne obojętne — metan CH4 i silan SiH4

Amoniak NH3 i fosforowodór PH3 — zasadowość wodorków 15. grupy

Wodorki tlenowców — woda H2O i siarkowodór H2S

Właściwości wodorków pierwiastków w grupach i okresach

Doświadczenie: badanie odczynu roztworów wodnych NH3 i HCl papierkiem wskaźnikowym

Reakcja amoniaku z chlorowodorem — synteza chlorku amonu w fazie gazowej

Wnioskowanie o charakterze wodorków na podstawie wyników doświadczeń

Budowa, klasyfikacja i właściwości chemiczne wodorków

Regla del octeto y estructuras de Lewis moleculares

Enlace iónico: formación, redes cristalinas y energía reticular

Enlace covalente polar y apolar

Enlace metálico y el modelo del mar de electrones

Teoría de repulsión de pares electrónicos (RPECV)

Polaridad molecular y momento dipolar

Fuerzas intermoleculares: dipolo-dipolo y dispersión de London

Puentes de hidrógeno y propiedades del agua

Relación entre enlace y propiedades macroscópicas

Enlace químico, geometría molecular y fuerzas intermoleculares

Determining Monatomic Ion Charges from Group Numbers

Essential Polyatomic Ions: Hydroxide, Nitrate, Sulfate, and Carbonate

Constructing Neutral Ionic Formulae with Polyatomic Ions

Using Brackets Correctly in Polyatomic Formulae

Deducing Unknown Ion Charges from Compound Formulae

Dissociation Equations for Soluble Salts in Water

GCSE Exam Mastery: Writing Complex Ionic Formulae

Ionic Formulae and Polyatomic Compounds

Asignación de números de oxidación en compuestos

Óxidos básicos y óxidos ácidos: formulación y nomenclatura

Hidróxidos o bases: formulación y nomenclatura

Hidrácidos y oxácidos: formulación y nomenclatura

Sales neutras, ácidas y básicas: formulación y nomenclatura

Hidruros metálicos y no metálicos

Taller integrado de nomenclatura inorgánica

Nomenclatura química inorgánica y formulación

Oxidation-Reduction Reactions and Electron Transfer

Activity Series of Metals and Single Displacement Reactions

Structure and Operation of Galvanic and Voltaic Cells

Standard Electrode Potentials and Cell Voltage Calculations

Predicting Feasibility of Redox Reactions Using Electrode Potentials

Writing Cathode Reduction Half-Equations for Molten Salts

Writing Anode Oxidation Half-Equations for Molten Salts

Electrolysis of Aqueous Solutions and Selective Discharge Rules

Industrial Applications of Electrolysis: Refining and Electroplating

Redox Reactions, Activity Series, and Electrochemistry

The Four State Symbols: Solid, Liquid, Gas, and Aqueous

Distinguishing Pure Liquids (l) from Aqueous Solutions (aq)

Assigning State Symbols in Precipitation Reactions

Assigning State Symbols in Gas-Evolving Reactions

State Symbols in Thermal Decomposition and Combustion

GCSE Exam Mastery: Writing Full Balanced Equations with State Symbols

State Symbols and Reaction Environments

Fluorowcowodory HF, HCl, HBr i HI — budowa i polaryzacja wiązania H–X

Rozpuszczalność gazowych chlorowcowodorów w wodzie — doświadczenie „fontanna chlorowodorowa”

Dysocjacja elektrolityczna kwasów chlorowcowodorowych i zmiana mocy kwasów w grupie 17

Specyficzne właściwości kwasu fluorowodorowego HF — trawienie szkła

Reakcje kwasów chlorowcowodorowych z zasadami — zapis cząsteczkowy i jonowy

Właściwości redukujące halogenowodorów — HCl, HBr i HI w reakcjach z utleniaczami

Otrzymywanie gazowego chlorowodoru z chlorku sodu i stężonego H2SO4

Wodorki fluorowców i kwasowość chlorowcowodorów

OGS.11.PS.RX.1

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