Question

Uranium can be isolated from its ores by dissolving it as UO₂(NO₃)₂, then separating it as solid UO₂(C₂O₄)·3H₂O. Addition of 0.4031 g of sodium oxalate, Na₂C₂O₄, to a solution containing 1.481 g of uranyl nitrate, UO₂(NO₃)₂, yields 1.073 g of solid UO₂(C₂O₄)·3H₂O.

a) Determine the moles of each substance.
b) Identify the limiting reactant.
c) Calculate the percent yield.
d) Measure reaction rates and optimize conditions.

Answer 1

a) The moles of each substance are determined by converting the given masses to moles using the molar masses.

b) The limiting reactant is identified by comparing the moles of each substance and using the stoichiometry of the reaction.

c) The percent yield is calculated by comparing the actual yield to the theoretical yield.

d) Measuring reaction rates and optimizing conditions typically involve monitoring concentrations and adjusting factors such as temperature and pressure.

Step-by-step explanation:

a) To determine the moles of each substance, we need to convert the given masses to moles using the molar masses. The molar mass of Na2C2O4 is 134.00 g/mol, and the molar mass of UO2(NO3)2 is 394.02 g/mol. For Na2C2O4, 0.4031 g is equal to 0.003 g of Na2C2O4 (0.4031 g / 134.00 g/mol). For UO2(NO3)2, 1.481 g is equal to 0.0038 g of UO2(NO3)2 (1.481 g / 394.02 g/mol).

b) To identify the limiting reactant, we compare the moles of each substance. From part a, we can see that there are 0.003 moles of Na2C2O4 and 0.0038 moles of UO2(NO3)2. Since the stoichiometry of the reaction is 1:1, the limiting reactant is Na2C2O4.

c) To calculate the percent yield, we need to compare the actual yield to the theoretical yield. From the given, actual yield = 1.073 g of UO2(C2O4)·3H2O. From the limiting reactant, the theoretical yield can be calculated as follows: 0.003 moles of Na2C2O4 will form 0.003 moles of UO2(C2O4)·3H2O, which is equal to 1.049 g (0.003 moles x 349.0 g/mol).

Finally, the percent yield is calculated using the formula: (actual yield / theoretical yield) x 100%. Substituting the values, we get: (1.073 g / 1.049 g) x 100% = 102.3%. Therefore, the percent yield is 102.3%.

d) The question mentions measuring reaction rates and optimizing conditions, but no specific details or data are provided. To measure reaction rates, one would typically monitor the concentration of reactants or products over time. Optimizing conditions would involve adjusting various factors such as temperature, pressure, and concentration to maximize the yield or rate of the reaction.