Lab 7

Determining the Formula of a Compound

A. Data Table (show completed data table here) (12 points)

|Measurements |Mass (in grams) |

|Mass of empty 100 mL beaker |55.45 g |

|Mass of zinc metal |1.80 g |

|Mass of beaker containing zinc chloride |58.16 g |

B. Follow-Up Questions (Show all work for calculations.)

1. Calculate the mass of zinc chloride produced. You know the original mass of the beaker. You also know the mass of the beaker plus the product you produced, which is zinc chloride. The difference between these two masses is the mass of zinc chlorine produced. Subtract the original mass of the beaker from the mass of the beaker plus the zinc chloride produced. Show your work. (20 points) Formula: (mass beaker + zinc chloride) - mass of beaker = mass of zinc chloride produced

58.16 – 55.45 = 2.71 g

2. Calculate mass of chlorine reacted. To do this, you know that the zinc and the hydrochloric acid combined to create zinc chloride. You know the mass of zinc used, and the mass of zinc chloride produced; so, the difference (subtract) between these values is the mass of chlorine reacted. (20 points) Formula: Mass of zinc chloride produced - mass of zinc used = mass of chloride reacted.

2.71 – 1.80 = 0.91 g

3. Calculate moles of zinc based on original mass of zinc. Show your calculations. (20 points) Formula: Mass Zn used x 1 mol Zn = moles of