How many grams of MgCl2 will be produced if you have 15 g of Mg(OH)2 and 50 g of HCl?

Answer 1

Hello!

To begin this problem, the very first thing we need to do is write and balance the chemical equation. We know that MgCl₂ is being produced and is therefore it is a product. We also that Mg(OH)₂ and HCl are reactants. This reaction is going to act like a double replacement reaction. Once it is balanced, it should look like this:

Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O

Now we have to find which of the reactants is the limiting reagent. To do this we will need to convert grams to moles for both reactants using molar mass.

15g Mg(OH)2 1 mol Mg(OH)2 1 mol MgCl2 95.205g MgCl2

Mg(OH)2: ——————x————————x———————x——————— = 24.49g MgCl2

1 58.33g Mg(OH)2 1 mol Mg(OH)2 1 mol MgCl2

50g HCl 1 mol HCl 1 mol MgCl₂ 95.205g MgCl₂

HCl: ——————x———————x——————x—————— = 65.28g MgCl₂

1 36.46g HCl 2 mol HCl 1 mol MgCl₂

We can see that Mg(OH)₂ is the limiting reagent because it yields less magnesium chloride than the HCl. So, our final answer is that after this reaction occurs, 24.49 grams of MgCl₂ will be produced.

I hope this helps! Don't be afraid to reach out if you need further explanation :)

Sorry the fractions aren't lined up very well, it is very difficult to get them perfect on here.