Question

Formula of precipitate SI(NO3)2(aq) + K3PO4(aq) Ba(NO3)2(aq) + MgSO4(aq) FeCl3(aq) + Pb(NO3)2(aq)-- H2SO4(aq) + Mg(OH)2(aq)— HNO3(aq) + Ba(OH)2(aq)—

formula precipitation

Answer 1

We know that all nitrates (salts with NO₃^- anion) are soluble. All sodium and potassium salts (salts with Na⁺ and K⁺) are also soluble. Most sulphates (salts with SO₄^2-) are soluble except PbSO₄, BaSO₄, Ag₂SO₄, SrSO₄ and CaSO₄. Most hydroxides (salts with OH^-) are slightly soluble except hydroxides of group I elements (NaOH, KOH etc.). Phosphates and carbonates (salts with PO₄^3- and CO₃^2-) are usually insoluble except those of sodium and potassium. Most chloride salts (salts containing Cl^-) are soluble except AgCl, PbCl₂ and Hg₂Cl₂.

Also in a double displacement (or replacement) reaction, there is a mutual exchange of ions between two compounds to form two new compounds.

1)

3Sr(NO3)2(aq) + 2K3PO4(aq) → Sr3(PO4)2(s) +6K NO3(aq)

This is the balanced chemical equation for reaction of Sr(NO₃)₂ with K₃PO₄. Here an insoluble Sr₃(PO₄)₂ is formed (a phosphate) and aqueous solution of KNO₃ is formed. So the formula of the solid formed is Sr₃(PO₄)₂.

2.

Ba(NO3)2(aq) + MgSO4(aq) + BaSO4(s) + Mg(NO3)2(aq)

This is the balanced chemical equation for reaction of Ba(NO₃)₂ with MgSO₄. Here an insoluble BaSO₄ is formed (a sulphate of Barium) and aqueous solution of Mg(NO₃)₂ is formed. So the formula of the solid formed is BaSO₄.

3.

2FeCl3(aq) + 3Pb(NO3)2(aq) + 3PbCl(s) +2Fe(NO3)2(aq)

This is the balanced chemical equation for reaction of FeCl₃ with Pb(NO₃)₂. Here an insoluble PbCl₂ is formed and aqueous solution of Fe(NO₃)₃ is formed. So the formula of the solid formed is PbCl₂.

4.

H2SO4(aq) + Mg(OH)2(aq) + MgSO4(aq) + 2H20(1)

This is a neutralisation reaction between sulphuric acid (H₂SO₄) and Magnesium hydroxide (Mg(OH)₂) to form aqueous solution of MgSO₄ and water. So there is no solid formed.

5.

2HNO3(aq) + Ba(OH)2(aq) + Ba(NO3)2(aq) + 2H20(1)

This is a neutralisation reaction between nitric acid (HNO₃) and Barium hydroxide (Ba(OH)₂) to form aqueous solution of Ba(NO₃)₂ and water. So there is no solid formed.

6.

CuCl(aq) + K2CO3(aq) + Cucoz(s) + 2K Cl(aq)

This is the balanced chemical equation for reaction of CuCl₂ with K₂CO₃. Here an insoluble CuCO₃ is formed (a carbonate of copper) and aqueous solution of KCl is formed. So the formula of the solid formed is CuCO₃.

7.

2KOH(aq) + Mn(NO3)2(aq) + Mn(OH)2(s) +2K NO3(aq)

This is the balanced chemical equation for reaction of Mn(NO₃)₂ with KOH. Here an insoluble Mn(OH)₂ is formed (a hydroxide of Mn) and aqueous solution of KNO₃ is formed. So the formula of the solid formed is Mn(OH)₂.

8.

Na2SO4(aq) + Ba(NO3)2(aq) + BaSO4(s) + 2NaNO3(aq)

This is the balanced chemical equation for reaction of Ba(NO₃)₂ with Na₂SO₄. Here an insoluble BaSO₄ is formed (a sulphate of Barium) and aqueous solution of NaNO₃ is formed. So the formula of the solid formed is BaSO₄.