Question

How many moles of H 2 can be formed if a 3.24 g sample of M g reacts with excess H C l ?

Answer 1

Answer:

0.135 mole of H2.

Explanation:

We'll begin by calculating the number of mole in 3.24 g of Mg. This can be obtained as follow:

Mass of Mg = 3.24 g

Molar mass of Mg = 24 g/mol

Mole of Mg =?

Mole = mass /Molar mass

Mole of Mg = 3.24/24

Mole of Mg = 0.135 mole

Next, we shall write the balanced equation for the reaction. This is illustrated below:

Mg + 2HCl —> MgCl2 + H2

From the balanced equation above,

1 mole of Mg reacted to produce 1 mole of H2.

Finally, we shall determine the number of mole of H2 produced by reacting 3.24 g (i.e 0.135 mole) of Mg. This can be obtained as follow:

From the balanced equation above,

1 mole of Mg reacted to produce 1 mole of H2.

Therefore, 0.135 mole of Mg will also react to produce 0.135 mole of H2.

Thus, 0.135 mole of H2 can be obtained from the reaction.