Experiment - Determination of a Chemical Reaction's Ratio

Introduction

When iron metal reacts with a dilute solution of copper(II) sulphate copper metal is displaced, as shown by the reactivity series.

If the exact mass of the iron metal used and the mass of the copper formed is known then their amounts can be worked out. From this information the ratio of iron to copper in the chemical equation can be calculated.

Method

Take a 100 cm3 beaker and weigh out accurately approximately 1 g of iron powder into it. Note down this mass in the table below.

Next add about 50 cm3 of the copper(II) sulphate solution provided to the beaker.

Stir the mixture carefully with a glass rod until all the dark grey iron powder appears to have reacted.

Filter the resulting mixture, using a filter funnel and paper, and rinse out the beaker with distilled water so you ensure all the solid is transferred to the filter paper. Then wash the solid residue with a little propanone to dry it.

Finally weigh the dried solid produced carefully.

Fill in the masses in the table below and calculate the other values.

Mass used/formed Amount used/formed Whole number ratio
Iron used      
Copper formed      

Use the whole number ratios in the table to construct a balanced equation for the reaction.

You can repeat the experiment using zinc powder instead of iron. See what whole number ratio is produced with that reaction.