3 M HCl solution was used to generate CO2 from the CaCO3 . What will be
the effect on the value reported for the molar volume of CO2 if 6 M HCl was used instead (too high,
too low, no difference)? Explain.
I have no idea what experiment you were performing; however, I can't see substituting 6M HCl for 3M HCl will have any effect other than requiring less acid to generate the CO2.
To determine the effect of using a 6 M HCl solution instead of a 3 M HCl solution on the reported molar volume of CO2, we need to understand the reaction that takes place between HCl and CaCO3.
The balanced equation for this reaction is:
CaCO3 (s) + 2 HCl (aq) → CaCl2 (aq) + H2O (l) + CO2 (g)
From the balanced equation, we can see that for every 2 moles of HCl, 1 mole of CO2 is produced. Therefore, the molar ratio between HCl and CO2 is 2:1.
Now, let's compare the two scenarios:
Scenario 1: Using 3 M HCl solution
In this case, we have a 3 M HCl solution, meaning there are 3 moles of HCl in 1 liter of solution. According to the molar ratio, for every 2 moles of HCl, we would expect to produce 1 mole of CO2. Therefore, the molar volume of CO2 can be determined by dividing the volume of CO2 evolved by the number of moles of CO2 produced, which would be half the number of moles of HCl used.
Scenario 2: Using 6 M HCl solution
In this case, we have a 6 M HCl solution, meaning there are 6 moles of HCl in 1 liter of solution. Following the same molar ratio, for every 2 moles of HCl, we would expect to produce 1 mole of CO2. However, since the concentration of HCl has doubled compared to scenario 1, the number of moles of HCl used would also be doubled. Therefore, the molar volume of CO2 can be determined by dividing the volume of CO2 evolved by the number of moles of CO2 produced, which would be the same as scenario 1.
In summary, using a 6 M HCl solution instead of a 3 M HCl solution will not have any effect on the value reported for the molar volume of CO2. The molar volume of CO2 depends on the number of moles of CO2 produced, which remains the same (assuming the amount of CaCO3 used and the reaction conditions remain constant). The concentration of HCl solution used only affects the number of moles of HCl used, but the molar ratio between HCl and CO2 remains unchanged.