Which of the chemical equations below are acid-base (proton transfer) reactions? select all that apply. mg(oh)2 (s) + h2so4 (aq) → mgso4 (s) + 2 h2o (l) fe(no3)3 (aq) + 3 koh (aq) → fe(oh)3 (s) + 3 kno3 (aq) zn (s) + cu(no3)2 (aq) → zn(no3)2 (aq) + cu (s) mg (s) + cu(no3)2 (aq) --> mg(no3)3 (aq) + cu (s) hcl (aq) + koh (aq) → kcl (aq) + h2o (l) nh3 (aq) + hcl (aq) → nh4cl (aq)?

Mg(OH)₂ (s) + H₂SO₄ → MgSO₄ (s)  + 2 H₂O (l).HCl (aq) + KOH (l) → KCl (aq) + H₂O (l).NH₃ (aq) + HCl (aq) → NH₄Cl (aq).Explanation

There are three acid-base theories: Arrhenius, Bronsted-Lowry, and Lewis. Among the three, only the Bronsted-Lowry theory defines acids and bases based on the transfer of protons H⁺.

A Bronsted-Lowry acid is a proton donor;A Bronsted-Lowry base is a proton acceptor.

Mg(OH)₂ (s) + H₂SO₄ → MgSO₄ (s)  + 2 H₂O (l)

Mg(OH)₂ acts as a base and accepts protons H⁺.H₂SO₄ acts as an acid and loses protons H⁺.

Fe(NO₃)₃ (aq) + 3 KOH (aq) → Fe(OH)₃ (s) + 3 KNO₃ (aq)

There's a transfer of OH⁻ and NO₃⁻ but not protons H⁺.

Zn (s) + Cu(NO₃)₂ (aq) → Zn(NO₃)₂ (aq) + Cu(s)

Zn loses electrons to Cu²⁺ in Cu(NO₃)₂.There's no transfer of protons H⁺.

Mg (s) + Cu(NO₃)₂ (aq) → Mg(NO₃)₂ + Cu (s)

Mg loses electrons to Cu²⁺ in Cu(NO₃)₂.There's no transfer of protons H⁺.

HCl (aq) + KOH (aq) → KCl (aq) + H₂O (l)

HCl acts as an acid and loses protons H⁺.KOH acts as a base and gains protons H⁺.

NH₃ (aq) + HCl (aq) → NH₄Cl (aq)

HCl acts as an acid and loses protons H⁺.NH₃ acts as a base and gains protons H⁺.

Cr(oh)3 -> cr(3+) + 3oh-