Final answer:
Chemical equations represent the reactants turning into products via a reaction. Example reactions show rubidium replacing magnesium in magnesium chloride to form rubidium chloride, and lead nitrate reacting with potassium iodide to form potassium nitrate and lead iodide precipitate.
Step-by-step explanation:
When discussing chemical reactions, it is important to correctly identify the reactants and products involved. In the case of rubidium (Rb) and magnesium chloride (MgCl2), the reaction provided as an example, 2Rb(s) + MgCl₂(s) → Mg(s) +2RbCl(s), shows the elements reacting to form new compounds.
For instance, in this aforementioned reaction, solid rubidium reacts with solid magnesium chloride. The result of this reaction is solid magnesium and solid rubidium chloride. This demonstrates an exchange reaction where the metal rubidium replaces the magnesium ion in magnesium chloride to form rubidium chloride.
The equation: 2KI (aq) + Pb(NO₃)₂ (aq) → 2KNO³ (aq) +Pbl₂ (s) is another reaction where lead nitrate reacts with potassium iodide in solution, yielding potassium nitrate in solution and a yellow precipitate of lead iodide.