Question

Calculate the molality of a solution formed by dissolving 27.8 g of lii in 500.0 ml of water.

Answer 1

The molality of the solution can be calculated using the formula: Molality (m) = moles of solute / mass of solvent (in kg). Given the mass of the solute and solvent, we can calculate the molality.

Step-by-step explanation:

The molality of a solution can be calculated using the formula:

Molality (m) = moles of solute / mass of solvent (in kg)

Given that 27.8 g of lii is dissolved in 500.0 mL of water, we need to convert the mass of water to kg:

Mass of water = 500.0 mL * 1 g/mL * 1 kg/1000 g = 0.500 kg

Now we can calculate the molality:

Molality (m) = moles of lii / 0.500 kg

Answer 2

Answer: Molarity of a solution : 0.416 M

`Molarity = ((Moles of solute))/((Volume of solution in L))`

In our question LiI(Lithium Iodide) is solute and we need to find the moles of LiI.

Given grams of LiI = 27.8g , Volume of solution = 500 mL

`Moles of LiI = (Grams)/(Molar mass)`

Molar mass of LiI = 133.85 g/mol

`Moles of LiI = (27.8g)/(133.85(g)/(mol))`

Moles of LiI = 0.208 mol

To find molarity we need volume of solution in 'L' , so we need to convert 500 mL to L.

1 L = 1000 mL

`(500 mL)* ((1L))/((1000mL))`

Volume = 0.5 L

`Molarity = ((Moles of solute))/((Volume of solution in L))`

`Molarity = ((0.208mol))/((0.5 L))`

Molarity =
`0.416(mol)/(L)` or 0.416 M