According to the collision theory, we can increase the rate of a reaction by increasing the concentration of reactants. We can also increase the rate of a reaction by increasing temperature to safe levels.
In the reaction mentioned in the question, Mg + 2HCl → MgCl2 + H2, if we increase the amount of magnesium or HCl, the reaction will proceed faster. Similarly, if we increase the temperature, then also the reaction rate will increase.
By increasing the concentration of reactants and the temperature
Explanation:
To increase the rat of collision between the reactants in this reaction, the concentration of reactants and temperature must be increases too.
The two most important factors that influence the frequency of collision and fraction of effective collision are the temperature of reaction and the concentration.
The number of effective collision is is proportional to the rate of reaction and eventually the concentration of reactants.
Also, the temperature at which the reaction is taking place is proportional to number of effective collision.
