What is the molarity of the following solutions?

A. 0.96 g MgCl2 in 500 mL solution
B. 9.33 g Na2S in 450 mL solution
C. 2.48 g CaF2 in 375 mL solution

To find the molarity of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters). Given the amount of solute in grams and the volume in milliliters, we need to convert the values to the required units before calculating the molarity.

A. 0.96 g MgCl2 in 500 mL solution
To find moles, we need to divide the mass of MgCl2 by its molar mass. The molar mass of MgCl2 is the sum of the atomic masses of magnesium (Mg) and chlorine (Cl):
1 mol MgCl2 = 24.31 g (Mg) + (2 x 35.45 g) (Cl) = 95.21 g/mol

First, convert the volume from milliliters to liters:
500 mL = 500/1000 = 0.5 L

Next, calculate the number of moles:
moles = mass (g) / molar mass (g/mol)
moles = 0.96 g / 95.21 g/mol = 0.0101 mol

Finally, divide the moles by the volume in liters to get the molarity:
Molarity = moles of solute (mol) / volume of solution (L)
Molarity = 0.0101 mol / 0.5 L = 0.0202 M

Therefore, the molarity of the solution is 0.0202 M.

B. 9.33 g Na2S in 450 mL solution
Follow the same steps as in part A to find the molarity of this solution.

First, convert the volume from milliliters to liters:
450 mL = 450/1000 = 0.45 L

Next, calculate the number of moles:
moles = mass (g) / molar mass (g/mol)
moles = 9.33 g / [22.99 g (Na) + 2 (32.07 g) (S)] = 0.1 mol

Finally, divide the moles by the volume in liters to get the molarity:
Molarity = moles of solute (mol) / volume of solution (L)
Molarity = 0.1 mol / 0.45 L = 0.22 M

Therefore, the molarity of the solution is 0.22 M.

C. 2.48 g CaF2 in 375 mL solution
Again, follow the same steps as in part A to find the molarity of this solution.

First, convert the volume from milliliters to liters:
375 mL = 375/1000 = 0.375 L

Next, calculate the number of moles:
moles = mass (g) / molar mass (g/mol)
moles = 2.48 g / [40.08 g (Ca) + 2 (19.00 g) (F)] = 0.0259 mol

Finally, divide the moles by the volume in liters to get the molarity:
Molarity = moles of solute (mol) / volume of solution (L)
Molarity = 0.0259 mol / 0.375 L = 0.0691 M

Therefore, the molarity of the solution is 0.0691 M.

To calculate the molarity of a solution, you need to know the number of moles of solute and the volume of the solution in liters.

First, let's calculate the number of moles for each solution:

A. For 0.96 g of MgCl2:
The molar mass of MgCl2 is 95.211 g/mol (24.305 g/mol for Mg + 2 * 35.453 g/mol for Cl).
moles of MgCl2 = mass / molar mass = 0.96 g / 95.211 g/mol = 0.01008 mol

B. For 9.33 g of Na2S:
The molar mass of Na2S is 78.045 g/mol (2 * 22.99 g/mol for Na + 32.06 g/mol for S).
moles of Na2S = mass / molar mass = 9.33 g / 78.045 g/mol = 0.1196 mol

C. For 2.48 g of CaF2:
The molar mass of CaF2 is 78.075 g/mol (40.08 g/mol for Ca + 2 * 18.998 g/mol for F).
moles of CaF2 = mass / molar mass = 2.48 g / 78.075 g/mol = 0.03177 mol

Now, we need to convert the volume of each solution to liters:

A. 500 mL = 500 mL / 1000 mL/L = 0.5 L
B. 450 mL = 450 mL / 1000 mL/L = 0.45 L
C. 375 mL = 375 mL / 1000 mL/L = 0.375 L

Finally, we can calculate the molarity using the formula:

molarity (M) = moles / volume (L)

A. Molarity of 0.96 g MgCl2 in 500 mL solution:
Molarity = 0.01008 mol / 0.5 L = 0.02016 M

B. Molarity of 9.33 g Na2S in 450 mL solution:
Molarity = 0.1196 mol / 0.45 L = 0.265 M

C. Molarity of 2.48 g CaF2 in 375 mL solution:
Molarity = 0.03177 mol / 0.375 L = 0.08472 M

Therefore, the molarity of the solutions are:
A. 0.02016 M
B. 0.265 M
C. 0.08472 M