The rate of reaction between magnesium and hydrochloric acid is affected by several factors, one of which is the surface area of the magnesium. The reaction between magnesium and hydrochloric acid can be represented by the following balanced chemical equation:Mg s + 2 HCl aq MgCl2 aq + H2 g In this reaction, magnesium Mg reacts with hydrochloric acid HCl to produce magnesium chloride MgCl2 and hydrogen gas H2 .The effect of surface area on the rate of reaction can be explained using the collision theory. According to this theory, for a reaction to occur, the reactant particles must collide with each other with sufficient energy and proper orientation. An increase in the surface area of a solid reactant, such as magnesium, exposes more of its particles to the other reactant in this case, hydrochloric acid , leading to more frequent collisions between the reactant particles.When the surface area of magnesium is increased, for example by using magnesium powder or thin strips instead of a large block, there is a greater chance of collisions between magnesium and hydrochloric acid particles. This results in an increased rate of reaction, as more magnesium particles are available to react with the hydrochloric acid at any given time.In summary, increasing the surface area of magnesium in a reaction with hydrochloric acid will increase the rate of reaction, as it allows for more frequent and effective collisions between the reactant particles.