Question

4.Calculate the molarity of a 3.5 L that contains 2.8 mol of HNO3.5.State the mass of the solute required to prepare 125 mL of 0.25 M Ba(NO3)2 solution.6.Calculate the concentration of a 60,0 mL solution that contains 0.075 mol of NH4Cl.7.Calculate the molarity of a 400.0 mL solution that contains 41.5 g of NaCl.8. What volume of 1.50 M KCl can be made from 550 g of KCI.9.Calculate the concentration of a 600.0 mL solution that contains 2.50 g of CaCO3.10. State the mass of the solute required to prepare 325 mL of a 1.5 M CuSO4.5 H2O solution.11. Calculate the molarity of a 200 mL solution that contains 1.2 x 1024 molecules of NaOH.12.How many moles of Cu(NO3)2 are contained in 400.0 mL of 0.90 M Cu(NO3)2.13. A 250.0 mL sample of 0.10 M Na2SO4 is evaporated to dryness. The resulting solid is thenweighed. What mass of solute would be recovered from the solution?

Answer 1

0.8M

Explanations:

The formula for calculating the molarity of a substance expressed as;

`molarity=(mole)/(volume)`

Given the following parameters

• mole of HNO3 = 2.8moles

,

• Volume of solution = 3.5L

Substitute the given parameters into the formula to have:

`\begin{gathered} molarity=(2.8moles)/(3.5L) \\ molarity=0.8M \end{gathered}`

Hence the molarity of a 3.5 L that contains 2.8 mol of HNO3 is 0.8M