Section Warm-Up
Journal: Prove It!
The illustration shows the mixing of two colorless aqueous solutions (lead nitrate and potassium iodide) in a sealed flask to form a yellow precipitate
(lead iodide) and a colorless solution (potassium nitrate). Record your answers to the following questions:
• What is meant by the phrase, “conservation of mass?”
• How would you prove that mass is conserved in this reaction?
• The equation that represents this reaction is Pb(NO3)2(aq) + 2 KI(aq) PbI2(s) + 2 KNO3(aq). In what ways does this equation show conservation
of mass?
