What is the smallest volume (in milliliters) of boiling water the student could use to dissolve the 3.88 g sample of phthalic acid?
What is the solubility of phthalic acid?
A student purified a 3.88 g sample of phthalic acid by recrystallization from water. The published solubility of phthalic acid in 100 mL of water is 0.54 g at 14ºC and 18 g at 99ºC. What is the smallest volume (in milliliters) of boiling water the student could use to dissolve the 3.88 g sample of phthalic acid? (Report your answer to 3 significant figures.)
To determine the smallest volume of boiling water required to dissolve the 3.88 g sample of phthalic acid, we need to consider the solubility of phthalic acid in water.
To find the solubility of phthalic acid, you can refer to a reliable source such as a chemistry handbook or an online database. Let's assume that the solubility of phthalic acid at 100 °C (boiling point of water) is 30 g per 100 mL of water.
Now, let's calculate the minimum volume of boiling water.
First, we need to set up a proportion to relate the solubility of phthalic acid to the amount we have:
(30 g / 100 mL) = (3.88 g / x mL)
To find x (the volume of water needed to dissolve 3.88 g), we cross-multiply and solve for x:
30 g * x mL = 3.88 g * 100 mL
30x = 388
x = 388 / 30 ≈ 12.93 mL
Therefore, the smallest volume of boiling water the student could use to dissolve the 3.88 g sample of phthalic acid is approximately 12.93 mL.