1. Calculate the number of moles of sulfuric acid that is contained in 250 mL of 8.500 M sulfuric acid solution

2. 7.300 moles of sodium nitrite are needed for a reaction. The solution is 5.450 M. How many mL are needed?

3. What mass (in g) of NH3 must be dissolved in 875 g of methanol to make a 0.430 molal solution?

4. Calculate the molality of a solution that is prepared by mixing 259.5 mL of CH3OH
(d = 0.792 g/mL) and 1387 mL of CH3CH2CH2OH (d = 0.811 g/mL)

5. A solution is prepared by dissolving 318.6 g sucrose (C12H22O11) in 4905 g of water. Determine the molarity of the solution

1.    2.125 moles

2.   1,339.45 mL

3.   6.1079 grams

4.   5.7026 M

5.   0.1898 mol/L

Explanation:

1. Molarity is defined as the number of moles of a substance per litre solution.

-Given the volume of the solution is 250 mL and 8.5 M of sulfuric acid, the moles is obtained as:

Hence, there are 2.125 moles of sulfuric acid in the solution.

2. Given 7.3 moles of sodium nitrate in a solution whose concentration is 5.45M.

#We apply the molarity formula to determine the solution's volume:

Hence, the volume of the solution is 1,339.45 mL

3. Given the mass of the solvent, methanol is 875 g and the molality of the solution is 0.430 m

#we apply the molality formula to calculate the mass of the solute :

Hence, the mass of the solute is 6.4079 grams

4. Given the densities as

We apply the molality formula to find the molality of the solution as follows:

Hence, the molality of the solution is 5.7026 M

5. Molarity is defined as the number of moles of a solute in a 1000 ml of a solution:

Hence, the molality of the solution is 0.1898 mol/L