Ответ:

  1. HF: H \(+1\), F \(-1\).
  2. Ba(OH)2: Ba \(+2\), O \(-2\), H \(+1\).
  3. N2O5: N \(+5\), O \(-2\).
  4. HNO3: H \(+1\), N \(+5\), O \(-2\).
  5. Fe(OH)3: Fe \(+3\), O \(-2\), H \(+1\).
  6. HgO: Hg \(+2\), O \(-2\).
  7. K3PO4: K \(+1\), P \(+5\), O \(-2\).
  8. B2O3: B \(+3\), O \(-2\).

Ответ: HF: H(+1), F(−1); Ba(OH)2: Ba(+2), O(−2), H(+1); N2O5: N(+5), O(−2); HNO3: H(+1), N(+5), O(−2); Fe(OH)3: Fe(+3), O(−2), H(+1); HgO: Hg(+2), O(−2); K3PO4: K(+1), P(+5), O(−2); B2O3: B(+3), O(−2).