Skip to main content
Pearson+ LogoPearson+ Logo

Molarity quiz #1 Flashcards

Molarity quiz #1
Control buttons has been changed to "navigation" mode.
1/40
  • How many grams of CaCl2 are in 250 mL of 2.0 M CaCl2 solution?
    First, calculate moles: 2.0 mol/L × 0.250 L = 0.5 mol. Molar mass of CaCl2 = 111 g/mol. 0.5 mol × 111 g/mol = 55.5 g.
  • Which solution is the most concentrated?
    The most concentrated solution is the one with the highest molarity (M), meaning the greatest number of moles of solute per liter of solution.
  • What are the units of molarity?
    Moles of solute per liter of solution (mol/L).
  • What are the units for molarity?
    Moles per liter (mol/L).
  • Why was it necessary to convert the concentration from mg/L to molarity?
    Because molarity (mol/L) is the standard unit for expressing solution concentration in chemistry, allowing for stoichiometric calculations.
  • What is the difference between molarity and molality?
    Molarity is moles of solute per liter of solution; molality is moles of solute per kilogram of solvent.
  • Which is a way to express concentration of a solution?
    Molarity (mol/L) is a common way to express solution concentration.
  • Which of the following solutions has the highest concentration?
    The solution with the highest molarity (M) has the highest concentration.
  • What is the molarity of a solution that contains 0.50 mole of NaOH in 0.50 liter of solution?
    M = 0.50 mol / 0.50 L = 1.0 M.
  • What is the relationship between solute amount and molarity?
    Molarity increases as the amount of solute per liter of solution increases.
  • What is the concentration of sodium ions in 0.300 M Na2CO3?
    Na2CO3 dissociates to give 2 Na+ per formula unit. [Na+] = 0.300 M × 2 = 0.600 M.
  • Which term is used to express the concentration of an aqueous solution?
    Molarity (M) is commonly used.
  • Which term describes a solution having a very well-known concentration of solute?
    A standard solution.
  • What is the molarity of 200 mL of solution in which 2.0 moles of sodium bromide is dissolved?
    M = 2.0 mol / 0.200 L = 10.0 M.
  • Which unit can be used to express solution concentration?
    Molarity (mol/L).
  • An acid has a molarity of 0.01 M. What does the 0.01 M refer to?
    It refers to 0.01 moles of acid per liter of solution.
  • What is the concentration of a solution made with 0.150 moles of KOH in 400.0 mL of solution?
    M = 0.150 mol / 0.400 L = 0.375 M.
  • What volume of a 1.5 M KOH solution is needed to provide 3.0 moles of KOH?
    Volume = 3.0 mol / 1.5 M = 2.0 L.
  • What are the common units for expressing solution concentration?
    Molarity (mol/L) is the most common.
  • Which of the following would give you the molarity of a solution?
    Dividing moles of solute by liters of solution.
  • What is the concentration of sodium ions in 0.300 M Na2SO4?
    Na2SO4 gives 2 Na+ per formula unit. [Na+] = 0.300 M × 2 = 0.600 M.
  • What is the concentration of a solution that contains 6 moles of solute in 2 liters of solution?
    M = 6 mol / 2 L = 3.0 M.
  • How many liters would you need to make a 1 M solution if you have 6 mol of sodium hydroxide?
    Volume = 6 mol / 1 M = 6 L.
  • What is the unit for molarity?
    Moles per liter (mol/L).
  • What is the molarity of a solution containing 28.6 grams of NH3 and a volume of 3.5 L?
    Moles NH3 = 28.6 g / 17.03 g/mol = 1.68 mol. M = 1.68 mol / 3.5 L = 0.48 M.
  • What is the molarity of Br− in each solution?
    For a solution of NaBr, [Br−] = molarity of NaBr. For CaBr2, [Br−] = 2 × molarity of CaBr2.
  • What is the unit of molarity?
    Moles per liter (mol/L).
  • What is the molarity of a solution containing 4 moles of KCl in 2.5 L of solution?
    M = 4 mol / 2.5 L = 1.6 M.
  • Which of the two acid solutions is more concentrated?
    The one with the higher molarity (M) is more concentrated.
  • What is the concentration of chloride ions in a 2.50 M solution of aluminum chloride?
    AlCl3 gives 3 Cl− per formula unit. [Cl−] = 2.50 M × 3 = 7.50 M.
  • What is the molarity of NO3− in each solution?
    For NaNO3, [NO3−] = molarity of NaNO3. For Mg(NO3)2, [NO3−] = 2 × molarity of Mg(NO3)2.
  • What is the concentration of sodium ions in 0.200 M Na3PO4?
    Na3PO4 gives 3 Na+ per formula unit. [Na+] = 0.200 M × 3 = 0.600 M.
  • How many sodium ions are present in 30.0 mL of 0.600 M Na2CO3 solution?
    Moles Na2CO3 = 0.600 mol/L × 0.030 L = 0.018 mol. Each gives 2 Na+: 0.018 mol × 2 = 0.036 mol Na+. Number of ions = 0.036 mol × 6.022×10^23 = 2.17×10^22 ions.
  • Which of the following solutions will have the greatest concentration?
    The solution with the highest molarity (M).
  • What is the concentration of H+ in a 0.025 M HCl solution?
    HCl dissociates completely, so [H+] = 0.025 M.
  • Which term refers to the number of moles of solute per liter of solution?
    Molarity.
  • What is the concentration of NaOH that is used?
    It is the molarity (mol/L) of the NaOH solution.
  • What are the units of concentration?
    Moles per liter (mol/L) for molarity.
  • What is the molar concentration of sulfate ions in a 0.150 M Na2SO4 solution?
    Na2SO4 gives 1 SO4^2− per formula unit. [SO4^2−] = 0.150 M.
  • What is the molarity of a solution that contains 3.25 moles of NaNO3 in 250 mL of solution?
    M = 3.25 mol / 0.250 L = 13.0 M.