calculate the average rate of a reaction. He placed 10.00 g piece of aluminium into 6.0 M HCl. After 20 s. he found that 4.50 g of unreacted magnesium remained. Calculate the average rate at which magnesium was consumed by the acid.

#not I really do not understand the aluminium and magneium

To calculate the average rate of a reaction, we need to determine the change in the concentration of a reactant over a given time period. In this case, we can use the change in the mass of the magnesium (Mg) to calculate its consumption rate.

First, let's clarify the elements involved in this reaction. The text provided refers to two different elements: aluminium (Al) and magnesium (Mg). However, the problem asks for the average rate at which magnesium was consumed by the acid. Therefore, we'll consider magnesium as the reactant in this reaction.

Now, let's break down the given information:

1. Initial mass of magnesium (Mg): 10.00 g
2. Mass of unreacted magnesium (Mg) after 20 seconds: 4.50 g

To calculate the change in mass of magnesium, we subtract the final mass from the initial mass:

Change in mass of magnesium = Initial mass - Final mass
= 10.00 g - 4.50 g
= 5.50 g

The change in mass of magnesium is equal to the amount consumed by the acid over 20 seconds.

To calculate the average rate of consumption of magnesium, we need to divide the change in mass by the time:

Average rate of magnesium consumption = Change in mass / Time
= 5.50 g / 20 s
= 0.275 g/s

Therefore, the average rate at which magnesium was consumed by the acid is 0.275 grams per second.