Answer:
0.394g
Step-by-step explanation:
At 78°C, you can dissolve, in 10mL of ethanol, 0.424g of the compound will dissolve. Then, you must filter the solution.
You take the filtrate of the solution in ethanol and cool it to 0°C. Om mL, only 0.03g of the compound will remain in solution. The other part is the purified compound.
Its mass (Theoretical yield) is:
0.424g - 0.030g =
0.394g