Final answer:
To determine the number of moles of magnesium chloride formed, we need to calculate the number of moles of magnesium formed. This can be done using the formula moles = mass / molar mass. Since the mole ratio between Mg(OH)₂ and MgCl₂ is 1:1, the number of moles of MgCl₂ formed is the same as the number of moles of magnesium formed.
Step-by-step explanation:
To determine the number of moles of magnesium chloride formed when 1.204 grams of Mg(OH)₂ is added to 55 ml of 0.70M HCl, we need to first write the balanced chemical equation for the reaction between Mg(OH)₂ and HCl. The equation is: Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O. From the balanced equation, we can see that the mole ratio between Mg(OH)₂ and MgCl₂ is 1:1. Therefore, the number of moles of MgCl₂ formed is equal to the number of moles of Mg(OH)₂ used. We can calculate the number of moles of Mg using the formula: moles = mass / molar mass. The molar mass of Mg(OH)₂ is 58.32 g/mol. Substitute the values into the formula: moles of Mg = 1.204 g / 58.32 g/mol. Calculate the value to get the number of moles of Mg. Finally, since the mole ratio is 1:1, the number of moles of MgCl₂ formed is also equal to the number of moles of Mg, which we calculated previously.