Question

In setting up this experiment, a student noticed that a bubble of air leaked into the syringe containing the hcl (aq) solution, but it was not taken into consideration for the volume added to the flask. what effect would this have on the measured volume of hydrogen gas? would the calculated molar volume of hydrogen be:

Answer 1

Yes This procedure effects measured volume of hydrogen gas .

Explanation:

Yes, there found the bubbles that are actually the evaporation of HCl gas which can be easily monitored by the help of Recorder or simply by the naked eye. Here we should set the assembly in such a way that these effects could be minimized.

However, hydrogen gas can not be ignored in such a way because it is lighter gas and if left open it will definitely affect the measured volume of hydrogen gas.

Answer 2

Experimentally, the molar volume of hydrogen gas is measured by reacting a piece of metal like magnesium with excess hydrochloric acid. The reaction which takes place is-

Mg (s) + 2HCl(aq)→ MgCl2(aq) + H2(g)

Since HCl is taken in excess, the limiting reagent is Mg. Thus, the molar volume of H2 formed would depend only on the number of moles of Mg.

Therefore, if a bubble leaked into a syringe containing HCl, that would not affect the measured volume or the molar volume of hydrogen gas.