Calculate the volume of gas you would expect to be evoleved if X mol of magnesium were reacted with an excess of HCl at standard conditions. Would the answer be X, 22.4X, or 22400X?
X what? 22.4X what? 22,400X what?
Mg + 2HCl ==> MgCl2 + H2
X mol Mg will produce X mol H2. 1 mol occupies 22.4L at STP; therefore, X mols will occupy 22.4X L at STP. So you could have two of the correct answers above if 22.4X is L and 22,400X is mL.
To calculate the volume of gas evolved when X moles of magnesium react with excess HCl at standard conditions, we need to consider the balanced chemical equation for the reaction.
The balanced equation for the reaction between magnesium and hydrochloric acid is:
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
From the equation, we can see that for every 1 mole of magnesium (Mg) reacted, 1 mole of hydrogen gas (H2) is produced.
According to the ideal gas law, one mole of any gas occupies 22.4 liters at standard temperature and pressure (STP) conditions.
Therefore, the volume of gas evolved when X moles of magnesium react with excess HCl would be X multiplied by 22.4 liters.
So, the answer would be 22.4X.