What mass of MgSO4 · 7H2O is required to

prepare 300 mL of a 0.61 M MgSO4 solution?
Answer in units of g

To calculate the mass of MgSO4 · 7H2O required, we need to know the molar mass of MgSO4 · 7H2O.

The molar mass of MgSO4 is 120.37 g/mol
The molar mass of H2O is 18.01528 g/mol

MgSO4 · 7H2O contains 7 molecules of H2O, so:
7 x 18.01528 g/mol = 126.106 g/mol

Now we can calculate the mass needed using the formula:

Mass (g) = Molar mass (g/mol) x Volume (L) x Concentration (mol/L)

First, convert the volume from mL to L:

300 mL = 300/1000 L = 0.3 L

Then, plug in the values into the formula:

Mass (g) = 126.106 g/mol x 0.3 L x 0.61 mol/L

Mass (g) = 23.126 g

Therefore, the mass of MgSO4 · 7H2O required to prepare 300 mL of a 0.61 M MgSO4 solution is approximately 23.126 g.

To determine the mass of MgSO4 · 7H2O (Magnesium Sulfate Heptahydrate) required, we'll first calculate the number of moles of MgSO4 needed. Then, we'll convert the moles to grams using the molar mass of MgSO4 · 7H2O.

Step 1: Calculate moles of MgSO4
Molar concentration (M) is expressed as moles of solute per liter of solution. So, we'll start by calculating the number of moles of MgSO4 using the given volume (300 mL) and molar concentration (0.61 M).

Moles = Volume (in liters) × Molar concentration
Moles = 300 mL × (1 L / 1000 mL) × 0.61 M
Moles = 0.183 moles of MgSO4

Step 2: Convert moles to grams
The molar mass of MgSO4 · 7H2O can be calculated by adding up the atomic masses of its elements:
Mg: 24.31 g/mol
S: 32.07 g/mol
O: 16.00 g/mol (for each of the 4 oxygens)
H: 1.01 g/mol (for each of the 14 hydrogens)
Add these masses together:
molar mass of MgSO4 · 7H2O = (24.31 g/mol) + (32.07 g/mol) + (16.00 g/mol × 4) + (1.01 g/mol × 14)

Now, use the molar mass to convert moles to grams:
Mass (g) = Moles × Molar mass
Mass (g) = 0.183 moles × [molar mass of MgSO4 · 7H2O]

Calculating the molar mass of MgSO4 · 7H2O gives:
molar mass of MgSO4 · 7H2O = 24.31 + 32.07 + (16.00 × 4) + (1.01 × 14)

Finally, substitute the molar mass value into the equation to find the mass of MgSO4 · 7H2O in grams.

How many mols MgSO4.7H2O do you want? That is M x L = ?

1 mol MgSO4 = 1 mol MgSO4.7H2O
Convert mols MgSO4.7H2O to grams. g = mols x molar mass MgSO4.7H2O