Comprehensive chemistry worksheet designed to help students practice writing formulas and naming various ions, covalent compounds, and acids.

It looks like you've uploaded a chemistry worksheet titled "Nomenclature and Chemical Compounds" with several sections. I’ll solve each part step by step and provide explanations.

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A. Write the correct formula for the following:

1. Copper(II) phosphate
- Copper(II) means Cu²⁺
- Phosphate is PO₄³⁻
- To balance charges: need 3 Cu²⁺ (total +6) and 2 PO₄³⁻ (total -6)
→ Cu₃(PO₄)₂

2. Nitric acid
- Nitric acid is HNO₃
→ HNO₃

3. Silver nitrate
- Silver is Ag⁺, nitrate is NO₃⁻
→ AgNO₃

4. Aluminum hydroxide
- Aluminum is Al³⁺, hydroxide is OH⁻
- Need 3 OH⁻ to balance Al³⁺
→ Al(OH)₃

5. Sulfuric acid
- Sulfuric acid is H₂SO₄
→ H₂SO₄

6. Copper(II) sulfate
- Copper(II) = Cu²⁺, sulfate = SO₄²⁻
→ CuSO₄

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B. Write the correct name for the following:

1. MgCl₂
- Magnesium ion = Mg²⁺, chloride = Cl⁻
→ Magnesium chloride

2. Na₂O
- Sodium = Na⁺, oxide = O²⁻
→ Sodium oxide

3. Pb(NO₃)₂
- Lead(II) because Pb²⁺ (since two NO₃⁻ ions), nitrate = NO₃⁻
→ Lead(II) nitrate

4. Al(NO₃)₃
- Aluminum = Al³⁺, nitrate = NO₃⁻
→ Aluminum nitrate

5. P₂O₅
- Covalent compound: phosphorus pentoxide
→ Diphosphorus pentoxide
*(Note: Common name is phosphorus pentoxide, but systematic name is diphosphorus pentoxide)*

6. Ca(OH)₂
- Calcium = Ca²⁺, hydroxide = OH⁻
→ Calcium hydroxide

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C. Correctly name the following as acids:

1. H₂SO₄
- Sulfuric acid (polyatomic ion: sulfate)
→ Sulfuric acid

2. HCl
- Hydrochloric acid (hydrogen + chlorine)
→ Hydrochloric acid

3. H₂CO₃
- Carbonic acid (carbonate ion)
→ Carbonic acid

4. H₃PO₄
- Phosphoric acid (phosphate ion)
→ Phosphoric acid

5. HNO₃
- Nitric acid (nitrate ion)
→ Nitric acid

6. HBr
- Hydrobromic acid (hydrogen + bromine)
→ Hydrobromic acid

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D. Write the correct formula for the following acids:

1. Nitric acid
→ HNO₃

2. Hydrofluoric acid
- Hydrogen + fluoride → HF
→ HF

3. Hydrochloric acid
→ HCl

4. Sulfuric acid
→ H₂SO₄

5. Bromic acid
- Bromate ion is BrO₃⁻ → HBrO₃
→ HBrO₃

6. Cyanic acid
- Cyanate ion is OCN⁻ → HOCN or HOCN
→ HOCN (or sometimes written as HOCN)

> Note: Cyanic acid is H–O–C≡N. It's a weak acid derived from cyanate ion.

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✔ Final Answer Summary:

#### A. Formulas:
1. Cu₃(PO₄)₂
2. HNO₃
3. AgNO₃
4. Al(OH)₃
5. H₂SO₄
6. CuSO₄

#### B. Names:
1. Magnesium chloride
2. Sodium oxide
3. Lead(II) nitrate
4. Aluminum nitrate
5. Diphosphorus pentoxide
6. Calcium hydroxide

#### C. Acid Names:
1. Sulfuric acid
2. Hydrochloric acid
3. Carbonic acid
4. Phosphoric acid
5. Nitric acid
6. Hydrobromic acid

#### D. Acid Formulas:
1. HNO₃
2. HF
3. HCl
4. H₂SO₄
5. HBrO₃
6. HOCN

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