Please help me answer these subunits! 12. Which the most useful unit of concentration for calculations involving the stoichiometry of reactions insolution?A. molalityB. molarityC. mole fractionD. percentage13. Knowing the concentration of solutes is important in controlling the stoichiometry of reactants for solutionreactions.A. TrueB. FalseC. MaybeD. Indefinite14. If 2.8 moles of Propane reacts with excess Oxygen gas how many grams of CO2 will be formed?1 C3H8 +50₂3CO2 + 4H₂OA. 244.4 g CO₂B. 369.6 g CO₂C. 636.8 g CO₂D. 969.8 g. CO₂15. Which described the colligative properties of solutions?A. They depend on the kind of solute.B. They depend on the amount of solvent.C. They depend of the nature of the solute particles.D. They depend on the number of solute particles in solution.16. Which colligative property is applied when ethyl glycol is added to the water in the radiator of a car?A. Osmotic pressureC. Freezing point depressionB. Vapor pressure elevationD. Boiling point of water in the radiator

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12. Which the most useful unit of concentration for calculations involving the stoichiometry of reactions in solution? A. molality B. molarity C. mole fraction D. percentage 13. Knowing the concentration of solutes is important in controlling the stoichiometry of reactants for solution reactions. A. True B. False C. Maybe D. Indefinite 14. If 2.8 moles of Propane reacts with excess Oxygen gas how many grams of CO₂ will be formed? 1 C3H8 + 50₂ 3CO₂ + 4H₂O A. 244.4 g CO2 B. 369.6 g CO₂ C. 636.8 g CO2 D. 969.8 g. CO₂