Answer:
108.3g
Explanation:
Given parameters:
Volume of solution = 570mm = 0.57L (1000mm = 1L)
Molarity of solution = 2M
Unknown
Mass of MgCl₂
Solution
We first find the number of moles in the given concentration of magnessium chloride using the expression below:
Number of moles of MgCl₂= Molarity x volume = 2 x 0.57 = 1.14moles
Using this known moles, we can the unknown mass of MgCl₂ the technician would require:
Mass of MgCl₂ required = number of moles of MgCl₂ x molar mass
Molar mass of MgCl₂:
Atomic mass of Cl = 35.5g
Atomic mass of Mg = 24g
MgCl₂ = 24 + (35.5x2) = 95gmol⁻¹
Mass of MgCl₂ required = 1.14mole x 95gmole⁻¹ = 108.3g