What factors affect the rate of reaction between magnesium ribbon and hydrochloric acid?

What factors affect the rate of reaction between magnesium ribbon and hydrochloric acid?

This chemistry coursework requires an investigation to see how long it takes for magnesium ribbon to be eaten away by hydrochloric acid.
Before starting the investigation, I decided to do some research about magnesium and hydrochloric acid.
Magnesium is a light, shiny grey metallic element, symbol Mg, atomic number 12, found in group two in the periodic table. It is quite reactive giving vigorous reactions towards acids. It is one of the alkaline earth metals, and the lightest of the commonly used metals. It is used in alloys, flash photography, flares, fireworks and flash bulbs because it burns vigorously in air with a bright white light. Magnesium reacts with steam to release hydrogen and it also burns in carbon dioxide gas.

Hydrochloric acid, HCl, is a solution of hydrogen chloride (a colourless acidic gas) in water. The concentrated acid is about 35% hydrogen chloride and is corrosive. ...