They are compounds Good Luck!
Answer:

Explanation:
1. Write the skeleton equation for the half-reaction
NO₃⁻ ⟶ N₂O
2. Balance all atoms other than H and O
2NO₃⁻ ⟶ N₂O
3. Balance O by adding H₂O molecules to the deficient side.
2NO₃⁻ ⟶ N₂O + 5H₂O
4. Balance H by adding H⁺ ions to the deficient side.
2NO₃⁻ + 10H⁺ ⟶ N₂O + 5H₂O
5. Balance charge by adding electrons to the deficient side.
2NO₃⁻ + 10H⁺ + 8e⁻ ⟶ N₂O + 5H₂O
The amount of charge required to reduce 2 mol of NO₃⁻ is 8 F

Ca₁₀(PO₄)₆(OH)₂ - hydroxyapatite
b. phosphorus (P) and calcium (Ca)
Hello!
The reduction in particle size results in an increased rate of solution. It occur because is harder for a a solvent to surround bigger molecules.
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