Worksheet on chemical formulae for educational purposes.

Problem Analysis:

The task involves two main parts:
1. Part 1: For each compound, determine the number of elements and the total number of atoms in the given chemical formula.
2. Part 2: Write the chemical formula for each compound based on the description of the number of atoms of each element.

Let's solve each part step by step.

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Part 1: Determine the Number of Elements and Atoms

#### Compound: Ammonia (NH₃)
- Formula: NH₃
- Elements: Nitrogen (N) and Hydrogen (H) → 2 elements
- Atoms: 1 N + 3 H = 4 atoms

#### Compound: Methane (CH₄)
- Formula: CH₄
- Elements: Carbon (C) and Hydrogen (H) → 2 elements
- Atoms: 1 C + 4 H = 5 atoms

#### Compound: Sodium Chloride (NaCl)
- Formula: NaCl
- Elements: Sodium (Na) and Chlorine (Cl) → 2 elements
- Atoms: 1 Na + 1 Cl = 2 atoms

#### Compound: Calcium Carbonate (CaCO₃)
- Formula: CaCO₃
- Elements: Calcium (Ca), Carbon (C), and Oxygen (O) → 3 elements
- Atoms: 1 Ca + 1 C + 3 O = 5 atoms

#### Compound: Sulfuric Acid (H₂SO₄)
- Formula: H₂SO₄
- Elements: Hydrogen (H), Sulfur (S), and Oxygen (O) → 3 elements
- Atoms: 2 H + 1 S + 4 O = 7 atoms

#### Compound: Sodium Bicarbonate (NaHCO₃)
- Formula: NaHCO₃
- Elements: Sodium (Na), Hydrogen (H), Carbon (C), and Oxygen (O) → 4 elements
- Atoms: 1 Na + 1 H + 1 C + 3 O = 6 atoms

#### Compound: Acetic Acid (CH₃COOH)
- Formula: CH₃COOH
- Elements: Carbon (C), Hydrogen (H), and Oxygen (O) → 3 elements
- Atoms: 2 C + 4 H + 2 O = 8 atoms

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Completed Table for Part 1:

| Compound | Formula | Number of Elements | Number of Atoms |
|------------------|------------|--------------------|-----------------|
| ammonia | NH₃ | 2 | 4 |
| methane | CH₄ | 2 | 5 |
| sodium chloride | NaCl | 2 | 2 |
| calcium carbonate| CaCO₃ | 3 | 5 |
| sulfuric acid | H₂SO₄ | 3 | 7 |
| sodium bicarbonate| NaHCO₃ | 4 | 6 |
| acetic acid | CH₃COOH | 3 | 8 |

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Part 2: Write the Formula for Each Compound

#### Compound: Hydrochloric Acid
- Description: 1 atom of hydrogen and 1 atom of chlorine
- Formula: HCl

#### Compound: Ethene
- Description: 2 atoms of carbon and 4 atoms of hydrogen
- Formula: C₂H₄

#### Compound: Aluminium Oxide
- Description: 2 atoms of aluminium and 3 atoms of oxygen
- Formula: Al₂O₃

#### Compound: Nitric Acid
- Description: 1 atom of hydrogen, 1 atom of nitrogen, and 3 atoms of oxygen
- Formula: HNO₃

#### Compound: Sodium Hydroxide
- Description: 1 atom of sodium, 1 atom of oxygen, and 1 atom of hydrogen
- Formula: NaOH

#### Compound: Glucose
- Description: 6 atoms of carbon, 12 atoms of hydrogen, and 6 atoms of oxygen
- Formula: C₆H₁₂O₆

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Completed Table for Part 2:

| Compound | Number of Atoms | Formula |
|------------------|------------------------------------------|-----------|
| hydrochloric acid| 1 atom of hydrogen and 1 atom of chlorine| HCl |
| ethene | 2 atoms of carbon and 4 atoms of hydrogen| C₂H₄ |
| aluminium oxide | 2 atoms of aluminium and 3 atoms of oxygen| Al₂O₃ |
| nitric acid | 1 atom of hydrogen, 1 atom of nitrogen, and 3 atoms of oxygen| HNO₃ |
| sodium hydroxide | 1 atom of sodium, 1 atom of oxygen, and 1 atom of hydrogen| NaOH |
| glucose | 6 atoms of carbon, 12 atoms of hydrogen, and 6 atoms of oxygen| C₆H₁₂O₆ |

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Final Answer:

Part 1:
| Compound | Formula | Number of Elements | Number of Atoms |
|------------------|------------|--------------------|-----------------|
| ammonia | NH₃ | 2 | 4 |
| methane | CH₄ | 2 | 5 |
| sodium chloride | NaCl | 2 | 2 |
| calcium carbonate| CaCO₃ | 3 | 5 |
| sulfuric acid | H₂SO₄ | 3 | 7 |
| sodium bicarbonate| NaHCO₃ | 4 | 6 |
| acetic acid | CH₃COOH | 3 | 8 |

Part 2:
| Compound | Number of Atoms | Formula |
|------------------|------------------------------------------|-----------|
| hydrochloric acid| 1 atom of hydrogen and 1 atom of chlorine| HCl |
| ethene | 2 atoms of carbon and 4 atoms of hydrogen| C₂H₄ |
| aluminium oxide | 2 atoms of aluminium and 3 atoms of oxygen| Al₂O₃ |
| nitric acid | 1 atom of hydrogen, 1 atom of nitrogen, and 3 atoms of oxygen| HNO₃ |
| sodium hydroxide | 1 atom of sodium, 1 atom of oxygen, and 1 atom of hydrogen| NaOH |
| glucose | 6 atoms of carbon, 12 atoms of hydrogen, and 6 atoms of oxygen| C₆H₁₂O₆ |

Boxed Final Answer:
\[
\boxed{
\begin{array}{|c|c|c|c|}
\hline
\text{Compound} & \text{Formula} & \text{Number of Elements} & \text{Number of Atoms} \\
\hline
\text{ammonia} & \text{NH}_3 & 2 & 4 \\
\text{methane} & \text{CH}_4 & 2 & 5 \\
\text{sodium chloride} & \text{NaCl} & 2 & 2 \\
\text{calcium carbonate} & \text{CaCO}_3 & 3 & 5 \\
\text{sulfuric acid} & \text{H}_2\text{SO}_4 & 3 & 7 \\
\text{sodium bicarbonate} & \text{NaHCO}_3 & 4 & 6 \\
\text{acetic acid} & \text{CH}_3\text{COOH} & 3 & 8 \\
\hline
\end{array}
}
\]
\[
\boxed{
\begin{array}{|c|c|c|}
\hline
\text{Compound} & \text{Number of Atoms} & \text{Formula} \\
\hline
\text{hydrochloric acid} & \text{1 atom of hydrogen and 1 atom of chlorine} & \text{HCl} \\
\text{ethene} & \text{2 atoms of carbon and 4 atoms of hydrogen} & \text{C}_2\text{H}_4 \\
\text{aluminium oxide} & \text{2 atoms of aluminium and 3 atoms of oxygen} & \text{Al}_2\text{O}_3 \\
\text{nitric acid} & \text{1 atom of hydrogen, 1 atom of nitrogen, and 3 atoms of oxygen} & \text{HNO}_3 \\
\text{sodium hydroxide} & \text{1 atom of sodium, 1 atom of oxygen, and 1 atom of hydrogen} & \text{NaOH} \\
\text{glucose} & \text{6 atoms of carbon, 12 atoms of hydrogen, and 6 atoms of oxygen} & \text{C}_6\text{H}_{12}\text{O}_6 \\
\hline
\end{array}
}
\]