The error of transferring zinc granules along with the copper instead of waiting for them to dissolve would give an incorrectly high calculated percentage recovery of copper metal. This is because the presence of zinc granules as an impurity would increase the total mass of the "recovered" material, leading to an overestimation of the copper recovery.
The error described in Part V, where the student transferred zinc granules along with the copper instead of waiting for them to dissolve, would give an incorrectly high calculated percentage recovery of copper metal.
Here's why:
1. Percentage recovery calculation: In this experiment, the percentage recovery of copper metal is calculated by dividing the mass of the recovered copper by the initial mass of the copper sample and multiplying by 100. The recovered copper is obtained by dissolving it in an acid solution and then separating it from any impurities, such as zinc granules.
2. Zinc granules interfere with the calculation: By transferring the zinc granules along with the copper, the student introduces an impurity that should not be included in the calculation. The presence of zinc granules would increase the total mass of the "recovered" material, leading to an overestimation of the copper recovery.
3. Inaccurate measurement of copper recovery: Since the zinc granules should have been left behind and not included in the recovered copper mass, their inclusion will artificially inflate the calculated percentage recovery. This means that the calculated recovery value will be higher than it should be, resulting in an incorrectly high calculated percentage recovery of copper metal.
The question probable may be:
Tell if error described below would give an incorrectly high or low calculated percentage recovery of copper metal: Explain your answer.
Some zinc granules remained and the student transferred them along with the copper, rather than waiting for them to dissolve.