# Does changing the volume of a reactant affect the rate of reaction? Does changing the volume of HCl affect the rate of a Mg & HCl reaction?

I'm doing a experiment in which I'm testing the affect of the concentration of a reactant on the rate of reaction.

The reaction is between Magnesium and Hydrochloric Acid and so I'm changing the concentration of $\ce{HCl}$ ($\ce{0.5~M}$, $\ce{1~M}$ etc.)

In my lab report, I'm writing a list of controlled variables. So far I've mentioned the surface area and temperature of reactants. I would like to know more controlled variables.

I want to know whether the volume of Hydrochloric Acid affects the rate of reaction when added to the same amount of Magnesium metal?

According to some it doesn't and some say it does; I'm confused.

Also, please tell me why or why not the $\ce{HCl}$ volume affects the rate of reaction.

If the concentration of $\ce{HCl}$ changes between trials and the volume changes between the trial as well, then is the rate of reaction affected?

Does volume affect concentration in this case?

• – Faded Giant Apr 7 '16 at 12:01
• The way you describe this represents a poorly designed experiment. You essentially have 2 variables; concentration and volume, if I understand you correctly. This is not advisable. If you were to see any effect, you wouldn't know if it were a result of volume or concentration. You should add the SAME volume of HCl of different concentrations. That way, only concentration varies. – Dr. J. May 26 '18 at 11:17