# Practice sets, with the answers on the second page.

Practice · ICSE / CBSE / SSLC · free

Free practice sheets for your board. Write the formula from the name, then balance the equation. The answers are at the end of each set, so you can mark your own work.

249 questions across the three boards. Every one is drawn from what that board's own textbooks set, and every answer is checked by this site's build. Pick your board and print the section.

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ICSE · Classes 6 to 9

## Indian Certificate of Secondary Education, set by the Council for the Indian School Certificate Examinations

0 formulas to write and 0 equations to balance, compiled from this board's own textbooks. The full chapter-by-chapter list is on [its syllabus page](/syllabus/icse/).

Answers — ICSE

Mark the set against these after it is finished, not during. If you are printing the sheet and want the answers on it, leave this block open before you print — it starts a new page.

CBSE · Classes 7 to 10

## Central Board of Secondary Education

79 formulas to write and 67 equations to balance, compiled from this board's own textbooks. The full chapter-by-chapter list is on [its syllabus page](/syllabus/cbse/).

### Write the formula

| No. | Name | Formula |
| --- | --- | --- |
| 1 | Acetic Acid |  |
| 2 | Aluminium Chloride |  |
| 3 | Aluminium Oxide |  |
| 4 | Aluminium Sulphate |  |
| 5 | Ammonium Chloride |  |
| 6 | Ammonium Sulphate |  |
| 7 | Barium Bromide |  |
| 8 | Barium Chloride |  |
| 9 | Barium Iodide |  |
| 10 | Barium Sulphate |  |
| 11 | Bleaching Powder |  |
| 12 | Calcium Bicarbonate |  |
| 13 | Calcium Carbonate |  |
| 14 | Calcium Chloride |  |
| 15 | Calcium Hydroxide |  |
| 16 | Calcium Nitrate |  |
| 17 | Calcium Oxide |  |
| 18 | Carbon Chloride |  |
| 19 | Carbon Dioxide |  |
| 20 | Carbon Monoxide |  |
| 21 | Copper [Cupric] Carbonate |  |
| 22 | Copper [Cupric] Chloride |  |
| 23 | Copper [Cupric] Hydroxide |  |
| 24 | Copper [Cupric] Oxide |  |
| 25 | Copper One Oxide |  |
| 26 | Copper One Sulphide |  |
| 27 | Copper Two Nitrate |  |
| 28 | Copper Two Sulphate |  |
| 29 | Hydrochloric Acid |  |
| 30 | Hydrogen Nitrate |  |
| 31 | Hydrogen Sulphate |  |
| 32 | Hydrogen Sulphide |  |
| 33 | Hydrogen Sulphite |  |
| 34 | Iron Three Oxide |  |
| 35 | Iron Two Chloride |  |
| 36 | Iron Two Sulphate |  |
| 37 | Iron Two Three Oxide |  |
| 38 | Lead [Plumbous] Chloride |  |
| 39 | Lead [Plumbous] Nitrate |  |
| 40 | Lead [Plumbous] Oxide |  |
| 41 | Magnesium Chloride |  |
| 42 | Magnesium Hydroxide |  |
| 43 | Magnesium Oxide |  |
| 44 | Manganese Four Oxide |  |
| 45 | Manganese Two Chloride |  |
| 46 | Mercury [Mercuric] Oxide |  |
| 47 | Mercury [Mercuric] Sulphide |  |
| 48 | Methanol |  |
| 49 | Nitrogen Dioxide |  |
| 50 | Nitrogen Hydride |  |
| 51 | Potassium Bromide |  |
| 52 | Potassium Carbonate |  |
| 53 | Potassium Hydroxide |  |
| 54 | Potassium Iodide |  |
| 55 | Potassium Nitrate |  |
| 56 | Potassium Oxide |  |
| 57 | Potassium Sulphate |  |
| 58 | Silver Bromide |  |
| 59 | Silver Chloride |  |
| 60 | Silver Nitrate |  |
| 61 | Sodium Aluminate |  |
| 62 | Sodium Bicarbonate |  |
| 63 | Sodium Carbonate |  |
| 64 | Sodium Chloride |  |
| 65 | Sodium Hydroxide |  |
| 66 | Sodium Nitrate |  |
| 67 | Sodium Oxide |  |
| 68 | Sodium Phosphate |  |
| 69 | Sodium Sulphate |  |
| 70 | Sodium Sulphide |  |
| 71 | Sodium Sulphite |  |
| 72 | Sodium Zincate |  |
| 73 | Sulphur Dioxide |  |
| 74 | Sulphur Trioxide |  |
| 75 | Zinc Carbonate |  |
| 76 | Zinc Nitrate |  |
| 77 | Zinc Oxide |  |
| 78 | Zinc Sulphate |  |
| 79 | Zinc Sulphide |  |

### Balance the equation

| No. | Equation | Condition |
| --- | --- | --- |
| 1 | HCl NaOH → NaCl H2O | — |
| 2 | MgO H2O → Mg(OH)2 | — |
| 3 | CO2 Ca(OH)2 → CaCO3 H2O | — |
| 4 | Cu H2O CO2 O2 → Cu(OH)2 CuCO3 | — |
| 5 | SO2 H2O → H2SO3 | — |
| 6 | CuSO4 Zn → ZnSO4 Cu | — |
| 7 | Zn H2SO4 → ZnSO4 H2 | — |
| 8 | Fe H2O → Fe3O4 H2 | steam |
| 9 | CO H2 → CH3OH | — |
| 10 | H2 Cl2 → HCl | — |
| 11 | BaCl2 Al2(SO4)3 → BaSO4 AlCl3 | — |
| 12 | Na H2O → NaOH H2 | — |
| 13 | BaCl2 Na2SO4 → BaSO4 NaCl | — |
| 14 | CaO H2O → Ca(OH)2 | — |
| 15 | C O2 → CO2 | — |
| 16 | H2 O2 → H2O | — |
| 17 | CH4 O2 → CO2 H2O | — |
| 18 | FeSO4 → Fe2O3 SO2 SO3 | heat |
| 19 | CaCO3 → CaO CO2 | heat |
| 20 | Pb(NO3)2 → PbO NO2 O2 | heat |
| 21 | AgCl → Ag Cl2 | sunlight |
| 22 | AgBr → Ag Br2 | sunlight |
| 23 | Fe CuSO4 → FeSO4 Cu | — |
| 24 | Pb CuCl2 → PbCl2 Cu | — |
| 25 | Cu O2 → CuO | — |
| 26 | CuO H2 → Cu H2O | — |
| 27 | ZnO C → Zn CO | — |
| 28 | MnO2 HCl → MnCl2 H2O Cl2 | — |
| 29 | Na O2 → Na2O | — |
| 30 | PbO C → Pb CO2 | — |
| 31 | Fe2O3 Al → Al2O3 Fe | — |
| 32 | NaOH H2SO4 → Na2SO4 H2O | — |
| 33 | H2 N2 → NH3 | — |
| 34 | H2S O2 → H2O SO2 | — |
| 35 | K H2O → KOH H2 | — |
| 36 | HNO3 Ca(OH)2 → Ca(NO3)2 H2O | — |
| 37 | NaCl AgNO3 → AgCl NaNO3 | — |
| 38 | BaCl2 H2SO4 → BaSO4 HCl | — |
| 39 | Zn AgNO3 → Zn(NO3)2 Ag | — |
| 40 | Al CuCl2 → AlCl3 Cu | — |
| 41 | BaCl2 K2SO4 → BaSO4 KCl | — |
| 42 | KBr BaI2 → KI BaBr2 | — |
| 43 | ZnCO3 → ZnO CO2 | — |
| 44 | Mg HCl → MgCl2 H2 | — |
| 45 | NaOH Zn → Na2ZnO2 H2 | — |
| 46 | Na2CO3 HCl → NaCl H2O CO2 | — |
| 47 | NaHCO3 HCl → NaCl H2O CO2 | — |
| 48 | CaCO3 H2O CO2 → Ca(HCO3)2 | — |
| 49 | NaCl H2O → NaOH Cl2 H2 | electrolysis |
| 50 | Ca(OH)2 Cl2 → CaOCl2 H2O | — |
| 51 | NaCl H2O CO2 NH3 → NH4Cl NaHCO3 | — |
| 52 | NaHCO3 → Na2CO3 H2O CO2 | heat |
| 53 | Al H2SO4 → Al2(SO4)3 H2 | — |
| 54 | Fe HCl → FeCl2 H2 | dilute acid |
| 55 | Al O2 → Al2O3 | — |
| 56 | Al2O3 HCl → AlCl3 H2O | — |
| 57 | Al2O3 NaOH → NaAlO2 H2O | — |
| 58 | Na2O H2O → NaOH | — |
| 59 | K2O H2O → KOH | — |
| 60 | Ca H2O → Ca(OH)2 H2 | — |
| 61 | Al H2O → Al2O3 H2 | — |
| 62 | HgS O2 → HgO SO2 | — |
| 63 | HgO → Hg O2 | heat |
| 64 | Cu2O Cu2S → Cu SO2 | — |
| 65 | ZnS O2 → ZnO SO2 | — |
| 66 | MnO2 Al → Mn Al2O3 | — |
| 67 | S O2 → SO2 | — |

Answers — CBSE

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| No. | Name | Formula | Built from |
| --- | --- | --- | --- |
| 1 | Acetic Acid | CH3COOH | Not built by the criss-cross rule |
| 2 | Aluminium Chloride | AlCl3 | Aluminium 3 · Chloride 1 |
| 3 | Aluminium Oxide | Al2O3 | Aluminium 3 · Oxide 2 |
| 4 | Aluminium Sulphate | Al2(SO4)3 | Aluminium 3 · Sulphate 2 |
| 5 | Ammonium Chloride | NH4Cl | Ammonium 1 · Chloride 1 |
| 6 | Ammonium Sulphate | (NH4)2SO4 | Ammonium 1 · Sulphate 2 |
| 7 | Barium Bromide | BaBr2 | Barium 2 · Bromide 1 |
| 8 | Barium Chloride | BaCl2 | Barium 2 · Chloride 1 |
| 9 | Barium Iodide | BaI2 | Barium 2 · Iodide 1 |
| 10 | Barium Sulphate | BaSO4 | Barium 2 · Sulphate 2 |
| 11 | Bleaching Powder | CaOCl2 | Not built by the criss-cross rule |
| 12 | Calcium Bicarbonate | Ca(HCO3)2 | Calcium 2 · Bicarbonate 1 |
| 13 | Calcium Carbonate | CaCO3 | Calcium 2 · Carbonate 2 |
| 14 | Calcium Chloride | CaCl2 | Calcium 2 · Chloride 1 |
| 15 | Calcium Hydroxide | Ca(OH)2 | Calcium 2 · Hydroxide 1 |
| 16 | Calcium Nitrate | Ca(NO3)2 | Calcium 2 · Nitrate 1 |
| 17 | Calcium Oxide | CaO | Calcium 2 · Oxide 2 |
| 18 | Carbon Chloride | CCl4 | Carbon 4 · Chloride 1 |
| 19 | Carbon Dioxide | CO2 | Carbon 4 · Oxide 2 |
| 20 | Carbon Monoxide | CO | Not built by the criss-cross rule |
| 21 | Copper [Cupric] Carbonate | CuCO3 | Copper [Cupric] 2 · Carbonate 2 |
| 22 | Copper [Cupric] Chloride | CuCl2 | Copper [Cupric] 2 · Chloride 1 |
| 23 | Copper [Cupric] Hydroxide | Cu(OH)2 | Copper [Cupric] 2 · Hydroxide 1 |
| 24 | Copper [Cupric] Oxide | CuO | Copper [Cupric] 2 · Oxide 2 |
| 25 | Copper One Oxide | Cu2O | Copper [Cuprous] 1 · Oxide 2 |
| 26 | Copper One Sulphide | Cu2S | Copper [Cuprous] 1 · Sulphide 2 |
| 27 | Copper Two Nitrate | Cu(NO3)2 | Copper [Cupric] 2 · Nitrate 1 |
| 28 | Copper Two Sulphate | CuSO4 | Copper [Cupric] 2 · Sulphate 2 |
| 29 | Hydrochloric Acid | HCl | Hydrogen 1 · Chloride 1 |
| 30 | Hydrogen Nitrate | HNO3 | Hydrogen 1 · Nitrate 1 |
| 31 | Hydrogen Sulphate | H2SO4 | Hydrogen 1 · Sulphate 2 |
| 32 | Hydrogen Sulphide | H2S | Hydrogen 1 · Sulphide 2 |
| 33 | Hydrogen Sulphite | H2SO3 | Hydrogen 1 · Sulphite 2 |
| 34 | Iron Three Oxide | Fe2O3 | Iron [Ferric] 3 · Oxide 2 |
| 35 | Iron Two Chloride | FeCl2 | Iron [Ferrous] 2 · Chloride 1 |
| 36 | Iron Two Sulphate | FeSO4 | Iron [Ferrous] 2 · Sulphate 2 |
| 37 | Iron Two Three Oxide | Fe3O4 | Not built by the criss-cross rule |
| 38 | Lead [Plumbous] Chloride | PbCl2 | Lead [Plumbous] 2 · Chloride 1 |
| 39 | Lead [Plumbous] Nitrate | Pb(NO3)2 | Lead [Plumbous] 2 · Nitrate 1 |
| 40 | Lead [Plumbous] Oxide | PbO | Lead [Plumbous] 2 · Oxide 2 |
| 41 | Magnesium Chloride | MgCl2 | Magnesium 2 · Chloride 1 |
| 42 | Magnesium Hydroxide | Mg(OH)2 | Magnesium 2 · Hydroxide 1 |
| 43 | Magnesium Oxide | MgO | Magnesium 2 · Oxide 2 |
| 44 | Manganese Four Oxide | MnO2 | Manganese 4 · Oxide 2 |
| 45 | Manganese Two Chloride | MnCl2 | Manganese 2 · Chloride 1 |
| 46 | Mercury [Mercuric] Oxide | HgO | Mercury [Mercuric] 2 · Oxide 2 |
| 47 | Mercury [Mercuric] Sulphide | HgS | Mercury [Mercuric] 2 · Sulphide 2 |
| 48 | Methanol | CH3OH | Not built by the criss-cross rule |
| 49 | Nitrogen Dioxide | NO2 | Not built by the criss-cross rule |
| 50 | Nitrogen Hydride | NH3 | Nitrogen 3 · Hydride 1 |
| 51 | Potassium Bromide | KBr | Potassium 1 · Bromide 1 |
| 52 | Potassium Carbonate | K2CO3 | Potassium 1 · Carbonate 2 |
| 53 | Potassium Hydroxide | KOH | Potassium 1 · Hydroxide 1 |
| 54 | Potassium Iodide | KI | Potassium 1 · Iodide 1 |
| 55 | Potassium Nitrate | KNO3 | Potassium 1 · Nitrate 1 |
| 56 | Potassium Oxide | K2O | Potassium 1 · Oxide 2 |
| 57 | Potassium Sulphate | K2SO4 | Potassium 1 · Sulphate 2 |
| 58 | Silver Bromide | AgBr | Silver 1 · Bromide 1 |
| 59 | Silver Chloride | AgCl | Silver 1 · Chloride 1 |
| 60 | Silver Nitrate | AgNO3 | Silver 1 · Nitrate 1 |
| 61 | Sodium Aluminate | NaAlO2 | Sodium 1 · Aluminate 1 |
| 62 | Sodium Bicarbonate | NaHCO3 | Sodium 1 · Bicarbonate 1 |
| 63 | Sodium Carbonate | Na2CO3 | Sodium 1 · Carbonate 2 |
| 64 | Sodium Chloride | NaCl | Sodium 1 · Chloride 1 |
| 65 | Sodium Hydroxide | NaOH | Sodium 1 · Hydroxide 1 |
| 66 | Sodium Nitrate | NaNO3 | Sodium 1 · Nitrate 1 |
| 67 | Sodium Oxide | Na2O | Sodium 1 · Oxide 2 |
| 68 | Sodium Phosphate | Na3PO4 | Sodium 1 · Phosphate 3 |
| 69 | Sodium Sulphate | Na2SO4 | Sodium 1 · Sulphate 2 |
| 70 | Sodium Sulphide | Na2S | Sodium 1 · Sulphide 2 |
| 71 | Sodium Sulphite | Na2SO3 | Sodium 1 · Sulphite 2 |
| 72 | Sodium Zincate | Na2ZnO2 | Sodium 1 · Zincate 2 |
| 73 | Sulphur Dioxide | SO2 | Not built by the criss-cross rule |
| 74 | Sulphur Trioxide | SO3 | Not built by the criss-cross rule |
| 75 | Zinc Carbonate | ZnCO3 | Zinc 2 · Carbonate 2 |
| 76 | Zinc Nitrate | Zn(NO3)2 | Zinc 2 · Nitrate 1 |
| 77 | Zinc Oxide | ZnO | Zinc 2 · Oxide 2 |
| 78 | Zinc Sulphate | ZnSO4 | Zinc 2 · Sulphate 2 |
| 79 | Zinc Sulphide | ZnS | Zinc 2 · Sulphide 2 |

| No. | Balanced |
| --- | --- |
| 1 | HCl NaOH → NaCl H2O |
| 2 | MgO H2O → Mg(OH)2 |
| 3 | CO2 Ca(OH)2 → CaCO3 H2O |
| 4 | 2Cu H2O CO2 O2 → Cu(OH)2 CuCO3 |
| 5 | SO2 H2O → H2SO3 |
| 6 | CuSO4 Zn → ZnSO4 Cu |
| 7 | Zn H2SO4 → ZnSO4 H2 |
| 8 | 3Fe 4H2O → Fe3O4 4H2 |
| 9 | CO 2H2 → CH3OH |
| 10 | H2 Cl2 → 2HCl |
| 11 | 3BaCl2 Al2(SO4)3 → 3BaSO4 2AlCl3 |
| 12 | 2Na 2H2O → 2NaOH H2 |
| 13 | BaCl2 Na2SO4 → BaSO4 2NaCl |
| 14 | CaO H2O → Ca(OH)2 |
| 15 | C O2 → CO2 |
| 16 | 2H2 O2 → 2H2O |
| 17 | CH4 2O2 → CO2 2H2O |
| 18 | 2FeSO4 → Fe2O3 SO2 SO3 |
| 19 | CaCO3 → CaO CO2 |
| 20 | 2Pb(NO3)2 → 2PbO 4NO2 O2 |
| 21 | 2AgCl → 2Ag Cl2 |
| 22 | 2AgBr → 2Ag Br2 |
| 23 | Fe CuSO4 → FeSO4 Cu |
| 24 | Pb CuCl2 → PbCl2 Cu |
| 25 | 2Cu O2 → 2CuO |
| 26 | CuO H2 → Cu H2O |
| 27 | ZnO C → Zn CO |
| 28 | MnO2 4HCl → MnCl2 2H2O Cl2 |
| 29 | 4Na O2 → 2Na2O |
| 30 | 2PbO C → 2Pb CO2 |
| 31 | Fe2O3 2Al → Al2O3 2Fe |
| 32 | 2NaOH H2SO4 → Na2SO4 2H2O |
| 33 | 3H2 N2 → 2NH3 |
| 34 | 2H2S 3O2 → 2H2O 2SO2 |
| 35 | 2K 2H2O → 2KOH H2 |
| 36 | 2HNO3 Ca(OH)2 → Ca(NO3)2 2H2O |
| 37 | NaCl AgNO3 → AgCl NaNO3 |
| 38 | BaCl2 H2SO4 → BaSO4 2HCl |
| 39 | Zn 2AgNO3 → Zn(NO3)2 2Ag |
| 40 | 2Al 3CuCl2 → 2AlCl3 3Cu |
| 41 | BaCl2 K2SO4 → BaSO4 2KCl |
| 42 | 2KBr BaI2 → 2KI BaBr2 |
| 43 | ZnCO3 → ZnO CO2 |
| 44 | Mg 2HCl → MgCl2 H2 |
| 45 | 2NaOH Zn → Na2ZnO2 H2 |
| 46 | Na2CO3 2HCl → 2NaCl H2O CO2 |
| 47 | NaHCO3 HCl → NaCl H2O CO2 |
| 48 | CaCO3 H2O CO2 → Ca(HCO3)2 |
| 49 | 2NaCl 2H2O → 2NaOH Cl2 H2 |
| 50 | Ca(OH)2 Cl2 → CaOCl2 H2O |
| 51 | NaCl H2O CO2 NH3 → NH4Cl NaHCO3 |
| 52 | 2NaHCO3 → Na2CO3 H2O CO2 |
| 53 | 2Al 3H2SO4 → Al2(SO4)3 3H2 |
| 54 | Fe 2HCl → FeCl2 H2 |
| 55 | 4Al 3O2 → 2Al2O3 |
| 56 | Al2O3 6HCl → 2AlCl3 3H2O |
| 57 | Al2O3 2NaOH → 2NaAlO2 H2O |
| 58 | Na2O H2O → 2NaOH |
| 59 | K2O H2O → 2KOH |
| 60 | Ca 2H2O → Ca(OH)2 H2 |
| 61 | 2Al 3H2O → Al2O3 3H2 |
| 62 | 2HgS 3O2 → 2HgO 2SO2 |
| 63 | 2HgO → 2Hg O2 |
| 64 | 2Cu2O Cu2S → 6Cu SO2 |
| 65 | 2ZnS 3O2 → 2ZnO 2SO2 |
| 66 | 3MnO2 4Al → 3Mn 2Al2O3 |
| 67 | S O2 → SO2 |

SSLC · Classes 8 to 10

## Secondary School Leaving Certificate, Kerala State syllabus

52 formulas to write and 51 equations to balance, compiled from this board's own textbooks. The full chapter-by-chapter list is on [its syllabus page](/syllabus/sslc/).

### Write the formula

| No. | Name | Formula |
| --- | --- | --- |
| 1 | Aluminium Chloride |  |
| 2 | Aluminium Hydroxide |  |
| 3 | Aluminium Oxide |  |
| 4 | Aluminium Sulphate |  |
| 5 | Ammonium Chloride |  |
| 6 | Ammonium Hydroxide |  |
| 7 | Barium Chloride |  |
| 8 | Barium Sulphate |  |
| 9 | Calcium Carbonate |  |
| 10 | Calcium Chloride |  |
| 11 | Calcium Hydroxide |  |
| 12 | Calcium Oxide |  |
| 13 | Calcium Sulphate |  |
| 14 | Carbon Dioxide |  |
| 15 | Carbon Monoxide |  |
| 16 | Copper Two Nitrate |  |
| 17 | Copper Two Sulphate |  |
| 18 | Hydrochloric Acid |  |
| 19 | Hydrogen Carbonate |  |
| 20 | Hydrogen Nitrate |  |
| 21 | Hydrogen Phosphate |  |
| 22 | Hydrogen Sulphate |  |
| 23 | Hydrogen Sulphite |  |
| 24 | Iron Two Chloride |  |
| 25 | Iron Two Sulphate |  |
| 26 | Magnesium Chloride |  |
| 27 | Magnesium Fluoride |  |
| 28 | Magnesium Hydroxide |  |
| 29 | Magnesium Nitrate |  |
| 30 | Magnesium Oxide |  |
| 31 | Magnesium Sulphate |  |
| 32 | Manganese Two Chloride |  |
| 33 | Nitrogen Dioxide |  |
| 34 | Nitrogen Hydride |  |
| 35 | Potassium Chlorate |  |
| 36 | Potassium Chloride |  |
| 37 | Potassium Hydroxide |  |
| 38 | Potassium Oxide |  |
| 39 | Potassium Permanganate |  |
| 40 | Potassium Phosphate |  |
| 41 | Silver Chloride |  |
| 42 | Silver Nitrate |  |
| 43 | Sodium Bromide |  |
| 44 | Sodium Chloride |  |
| 45 | Sodium Hydride |  |
| 46 | Sodium Hydroxide |  |
| 47 | Sodium Nitrate |  |
| 48 | Sulphur Dioxide |  |
| 49 | Sulphur Trioxide |  |
| 50 | Zinc Chloride |  |
| 51 | Zinc Oxide |  |
| 52 | Zinc Sulphate |  |

### Balance the equation

| No. | Equation | Condition |
| --- | --- | --- |
| 1 | Zn HCl → ZnCl2 H2 | — |
| 2 | C O2 → CO2 | — |
| 3 | H2 Cl2 → HCl | — |
| 4 | H2 O2 → H2O | — |
| 5 | Mg O2 → MgO | — |
| 6 | N2 H2 → NH3 | — |
| 7 | H2O2 → H2O O2 | — |
| 8 | CH4 O2 → CO2 H2O | — |
| 9 | N2 O2 → NO | — |
| 10 | CaCO3 → CaO CO2 | heat |
| 11 | H2 I2 → HI | — |
| 12 | Fe HCl → FeCl2 H2 | — |
| 13 | CO2 C → CO | — |
| 14 | Mg HCl → MgCl2 H2 | — |
| 15 | Na H2O → NaOH H2 | — |
| 16 | Al HCl → AlCl3 H2 | — |
| 17 | Al O2 → Al2O3 | — |
| 18 | SO2 O2 → SO3 | — |
| 19 | BaCl2 H2SO4 → BaSO4 HCl | — |
| 20 | Mg Cl2 → MgCl2 | — |
| 21 | Mg F2 → MgF2 | — |
| 22 | Na Cl2 → NaCl | — |
| 23 | CaCO3 HCl → CaCl2 H2O CO2 | — |
| 24 | MgO H2O → Mg(OH)2 | — |
| 25 | CaO H2O → Ca(OH)2 | — |
| 26 | NaOH HCl → NaCl H2O | — |
| 27 | Mg(OH)2 H2SO4 → MgSO4 H2O | — |
| 28 | Zn H2SO4 → ZnSO4 H2 | — |
| 29 | Mg HNO3 → Mg(NO3)2 H2 | — |
| 30 | Zn CuSO4 → ZnSO4 Cu | — |
| 31 | NaBr Cl2 → NaCl Br2 | — |
| 32 | S O2 → SO2 | — |
| 33 | H2 S → H2S | — |
| 34 | Na H2 → NaH | — |
| 35 | NaCl → Na Cl2 | electrolysis |
| 36 | KClO3 → KCl O2 | heat |
| 37 | NO O2 → NO2 | — |
| 38 | KMnO4 HCl → KCl MnCl2 H2O Cl2 | — |
| 39 | Cl2 H2O → HCl HOCl | — |
| 40 | NaCl AgNO3 → AgCl NaNO3 | — |
| 41 | Na2SO4 BaCl2 → BaSO4 NaCl | — |
| 42 | KCl AgNO3 → AgCl KNO3 | — |
| 43 | ZnSO4 BaCl2 → BaSO4 ZnCl2 | — |
| 44 | H2O → H2 O2 | electrolysis |
| 45 | FeSO4 Zn → ZnSO4 Fe | — |
| 46 | AgNO3 Cu → Cu(NO3)2 Ag | — |
| 47 | NH4Cl Ca(OH)2 → CaCl2 H2O NH3 | — |
| 48 | NH3 H2O → NH4OH | — |
| 49 | NH3 HCl → NH4Cl | — |
| 50 | C H2SO4 → CO2 H2O SO2 | — |
| 51 | Cu H2SO4 → CuSO4 SO2 H2O | — |

Answers — SSLC

Mark the set against these after it is finished, not during. If you are printing the sheet and want the answers on it, leave this block open before you print — it starts a new page.

| No. | Name | Formula | Built from |
| --- | --- | --- | --- |
| 1 | Aluminium Chloride | AlCl3 | Aluminium 3 · Chloride 1 |
| 2 | Aluminium Hydroxide | Al(OH)3 | Aluminium 3 · Hydroxide 1 |
| 3 | Aluminium Oxide | Al2O3 | Aluminium 3 · Oxide 2 |
| 4 | Aluminium Sulphate | Al2(SO4)3 | Aluminium 3 · Sulphate 2 |
| 5 | Ammonium Chloride | NH4Cl | Ammonium 1 · Chloride 1 |
| 6 | Ammonium Hydroxide | NH4OH | Ammonium 1 · Hydroxide 1 |
| 7 | Barium Chloride | BaCl2 | Barium 2 · Chloride 1 |
| 8 | Barium Sulphate | BaSO4 | Barium 2 · Sulphate 2 |
| 9 | Calcium Carbonate | CaCO3 | Calcium 2 · Carbonate 2 |
| 10 | Calcium Chloride | CaCl2 | Calcium 2 · Chloride 1 |
| 11 | Calcium Hydroxide | Ca(OH)2 | Calcium 2 · Hydroxide 1 |
| 12 | Calcium Oxide | CaO | Calcium 2 · Oxide 2 |
| 13 | Calcium Sulphate | CaSO4 | Calcium 2 · Sulphate 2 |
| 14 | Carbon Dioxide | CO2 | Carbon 4 · Oxide 2 |
| 15 | Carbon Monoxide | CO | Not built by the criss-cross rule |
| 16 | Copper Two Nitrate | Cu(NO3)2 | Copper [Cupric] 2 · Nitrate 1 |
| 17 | Copper Two Sulphate | CuSO4 | Copper [Cupric] 2 · Sulphate 2 |
| 18 | Hydrochloric Acid | HCl | Hydrogen 1 · Chloride 1 |
| 19 | Hydrogen Carbonate | H2CO3 | Hydrogen 1 · Carbonate 2 |
| 20 | Hydrogen Nitrate | HNO3 | Hydrogen 1 · Nitrate 1 |
| 21 | Hydrogen Phosphate | H3PO4 | Hydrogen 1 · Phosphate 3 |
| 22 | Hydrogen Sulphate | H2SO4 | Hydrogen 1 · Sulphate 2 |
| 23 | Hydrogen Sulphite | H2SO3 | Hydrogen 1 · Sulphite 2 |
| 24 | Iron Two Chloride | FeCl2 | Iron [Ferrous] 2 · Chloride 1 |
| 25 | Iron Two Sulphate | FeSO4 | Iron [Ferrous] 2 · Sulphate 2 |
| 26 | Magnesium Chloride | MgCl2 | Magnesium 2 · Chloride 1 |
| 27 | Magnesium Fluoride | MgF2 | Magnesium 2 · Fluoride 1 |
| 28 | Magnesium Hydroxide | Mg(OH)2 | Magnesium 2 · Hydroxide 1 |
| 29 | Magnesium Nitrate | Mg(NO3)2 | Magnesium 2 · Nitrate 1 |
| 30 | Magnesium Oxide | MgO | Magnesium 2 · Oxide 2 |
| 31 | Magnesium Sulphate | MgSO4 | Magnesium 2 · Sulphate 2 |
| 32 | Manganese Two Chloride | MnCl2 | Manganese 2 · Chloride 1 |
| 33 | Nitrogen Dioxide | NO2 | Not built by the criss-cross rule |
| 34 | Nitrogen Hydride | NH3 | Nitrogen 3 · Hydride 1 |
| 35 | Potassium Chlorate | KClO3 | Potassium 1 · Chlorate 1 |
| 36 | Potassium Chloride | KCl | Potassium 1 · Chloride 1 |
| 37 | Potassium Hydroxide | KOH | Potassium 1 · Hydroxide 1 |
| 38 | Potassium Oxide | K2O | Potassium 1 · Oxide 2 |
| 39 | Potassium Permanganate | KMnO4 | Potassium 1 · Permanganate 1 |
| 40 | Potassium Phosphate | K3PO4 | Potassium 1 · Phosphate 3 |
| 41 | Silver Chloride | AgCl | Silver 1 · Chloride 1 |
| 42 | Silver Nitrate | AgNO3 | Silver 1 · Nitrate 1 |
| 43 | Sodium Bromide | NaBr | Sodium 1 · Bromide 1 |
| 44 | Sodium Chloride | NaCl | Sodium 1 · Chloride 1 |
| 45 | Sodium Hydride | NaH | Sodium 1 · Hydride 1 |
| 46 | Sodium Hydroxide | NaOH | Sodium 1 · Hydroxide 1 |
| 47 | Sodium Nitrate | NaNO3 | Sodium 1 · Nitrate 1 |
| 48 | Sulphur Dioxide | SO2 | Not built by the criss-cross rule |
| 49 | Sulphur Trioxide | SO3 | Not built by the criss-cross rule |
| 50 | Zinc Chloride | ZnCl2 | Zinc 2 · Chloride 1 |
| 51 | Zinc Oxide | ZnO | Zinc 2 · Oxide 2 |
| 52 | Zinc Sulphate | ZnSO4 | Zinc 2 · Sulphate 2 |

| No. | Balanced |
| --- | --- |
| 1 | Zn 2HCl → ZnCl2 H2 |
| 2 | C O2 → CO2 |
| 3 | H2 Cl2 → 2HCl |
| 4 | 2H2 O2 → 2H2O |
| 5 | 2Mg O2 → 2MgO |
| 6 | N2 3H2 → 2NH3 |
| 7 | 2H2O2 → 2H2O O2 |
| 8 | CH4 2O2 → CO2 2H2O |
| 9 | N2 O2 → 2NO |
| 10 | CaCO3 → CaO CO2 |
| 11 | H2 I2 → 2HI |
| 12 | Fe 2HCl → FeCl2 H2 |
| 13 | CO2 C → 2CO |
| 14 | Mg 2HCl → MgCl2 H2 |
| 15 | 2Na 2H2O → 2NaOH H2 |
| 16 | 2Al 6HCl → 2AlCl3 3H2 |
| 17 | 4Al 3O2 → 2Al2O3 |
| 18 | 2SO2 O2 → 2SO3 |
| 19 | BaCl2 H2SO4 → BaSO4 2HCl |
| 20 | 2Mg 2Cl2 → 2MgCl2 |
| 21 | 2Mg 2F2 → 2MgF2 |
| 22 | 2Na Cl2 → 2NaCl |
| 23 | CaCO3 2HCl → CaCl2 H2O CO2 |
| 24 | MgO H2O → Mg(OH)2 |
| 25 | CaO H2O → Ca(OH)2 |
| 26 | NaOH HCl → NaCl H2O |
| 27 | Mg(OH)2 H2SO4 → MgSO4 2H2O |
| 28 | Zn H2SO4 → ZnSO4 H2 |
| 29 | Mg 2HNO3 → Mg(NO3)2 H2 |
| 30 | Zn CuSO4 → ZnSO4 Cu |
| 31 | 2NaBr Cl2 → 2NaCl Br2 |
| 32 | S O2 → SO2 |
| 33 | H2 S → H2S |
| 34 | 2Na H2 → 2NaH |
| 35 | 2NaCl → 2Na Cl2 |
| 36 | 2KClO3 → 2KCl 3O2 |
| 37 | 2NO O2 → 2NO2 |
| 38 | 2KMnO4 16HCl → 2KCl 2MnCl2 8H2O 5Cl2 |
| 39 | Cl2 H2O → HCl HOCl |
| 40 | NaCl AgNO3 → AgCl NaNO3 |
| 41 | Na2SO4 BaCl2 → BaSO4 2NaCl |
| 42 | KCl AgNO3 → AgCl KNO3 |
| 43 | ZnSO4 BaCl2 → BaSO4 ZnCl2 |
| 44 | 2H2O → 2H2 O2 |
| 45 | FeSO4 Zn → ZnSO4 Fe |
| 46 | 2AgNO3 Cu → Cu(NO3)2 2Ag |
| 47 | 2NH4Cl Ca(OH)2 → CaCl2 2H2O 2NH3 |
| 48 | NH3 H2O → NH4OH |
| 49 | NH3 HCl → NH4Cl |
| 50 | C 2H2SO4 → CO2 2H2O 2SO2 |
| 51 | Cu 2H2SO4 → CuSO4 SO2 2H2O |

## Where these come from, and what they are not.

Every question above is generated from the inventories on [the syllabus pages](/syllabus/) — the formulas and equations each board's own textbooks set, compiled chapter by chapter by the author of the Playbook. The formulas are checked against the criss-cross rule and the equations are atom-counted, on every build of this site.

**None of it is taken from the book.** [_The Language of Chemistry, Playbook®_](/playbooks/language-of-chemistry/) contains 19 exercises and 279 questions of its own, and those stay in the book. That is the reason this page can be given away without a form attached to it — and the reason it is not a substitute for the book, which is gated, marked and sequenced in a way a printed sheet cannot be. Printing and copying are covered on [the copyright page](/legal/copyright/).

Two CBSE Class 7 equations are missing from the set above on purpose: the textbook prints them unbalanced, so there is no answer to mark against. Both are shown, counted, and explained on [the balancing page](/balancing-chemical-equations/).

## Questions

**Do I have to give an email address to get these?**

No. There is no form on this page, nothing to sign up for and nothing to download. The questions and the answers are both on the page, and the page prints.

**Where do these questions come from?**

From each board’s own syllabus: every formula and every equation the ICSE, CBSE and Kerala SSLC textbooks set, compiled chapter by chapter. None of them is taken from The Language of Chemistry, Playbook® — the book’s own exercises stay in the book.

**Can I print these for my class?**

Yes. This page is set up to print, and its questions are drawn from published syllabuses rather than from the Playbook. Photocopying the Playbook itself is a different matter and is covered on the copyright page.

**Why are the answers hidden?**

Because an answer a student can see while attempting the question is not a question. Open the answers after the set is finished, and mark it then.

## A sheet is practice. The book is a sequence.

Anyone can hand a student a worksheet. What this page cannot do is stop them going on to equations while the valencies are still being guessed at — and that is the whole of the Playbook's argument: the chapter does not open until the score is made, and below the score the exercises are repeated.

The Playbook open to Activity V and VI: fifteen green radical tokens printed in three valency columns on the left, and on the right a grid of exercise boxes with the first few filled in by pencil.

[See how the method works](/method/) [Using it at home](/for-parents/) [Teaching it in class](/for-teachers/)