Chapter 11 Question

Question

a) Magnesium forms the compounds Mg(NO₃)₂, MgCl₂, MgCO₃, and Mg₃(PO₄)₂. Write the formulas for barium nitrate, barium chloride, barium carbonate, and barium nitrate. Explain why the formulas look this way? 

b) Knowing that aluminum forms a +3 charge, what would you predict are the formulas for aluminum nitrate, aluminum chloride, aluminum carbonate, and aluminum phosphate?



c) Give the preferred names for: K₂SO₄, (NH₄)₂SO₄, Na₂S, H₂S, SO₃, P₂O₅, Ba₃N₂, SiF₄, S₂Cl₂.

Answer 1

(a) Ba(NO₃)₂, BaCl₂, BaCO₃, and Ba₃(PO₄)₂ (assuming the last is barium phosphate instead of repeating barium nitrate)

since the element Ba forms Ba²⁺ ions just like Mg (since they are both in the same periodic table group).

(b) Al(NO₃)₃, AlCl₃, Al₂(CO₃)₃, and AlPO₄

since the element Al forms Al³⁺ ions (based on its position in the periodic table).

(c) K₂SO₄ is potassium sulfate

(NH₄)₂SO₄ is ammonium sulfate

Na₂S is sodium sulfide

H₂S is hydrogen sulfide

SO₃ is sulfur trioxide

P₂O₅ is phosphorus pentoxide (sometimes named diphosphorus pentoxide)

Ba₃N₂ is barium nitride

SiF₄, is silicon tetrafluoride (sometimes named tetrafluorosilane)

S₂Cl₂ is disulfur dichloride (sometimes named dichlorodisulfane)