Question

if I have the reaction
Magnesium + Hydrochloric Acid -> Magnesium Chloride + Hydrogen Gas
And I have to 'investigate the effect of the concentration of the acid on the volume of hydrogen gas produced in the above reaction',
what would be expected to happen?

Answer 1

I would expect the HCL to be diluted with water, so the complete reaction would be...

Mg+ water>hydrogen gas + magnesium hydroxide in addidtion to the reaction you wrote.

I expect the acid reaction to be faster, so as it is diluted, you notice the rate decreases. However, the water recaction slow as it is, will occur.

Try a piece of Mg in water (warm) and look at the bubbles...

You are dealing wiht a combination of two reactions when deluting.