Question

a chemistry student weighs out 9.00 g of an unknown solid compound x and adds it to 100. ml of distilled water at 19.°c. after 10 minutes of stirring, all of the x has dissolved. just to be sure, the student adds a further 20. mg of x to the solution, and it, too, dissolves. using only the information above, can you calculate the solubility of x in water at 19.°c? if you said yes, calculate it. be sure your answer has a unit symbol and the right number of significant digits. no yes

Explanation:

Step1: Determine the formula for solubility

Solubility is defined as the mass of solute per volume of solvent. Here, the mass of \(X\) is \(9.00\ g+ 20\times10^{- 3}\ g=9.02\ g\) (converting \(20\ mg\) to \(g\): \(20\ mg = 20\times10^{-3}\ g\)), and the volume of water is \(100\ mL\).

Step2: Calculate the solubility

The formula for solubility \(S=\frac{m}{V}\), where \(m\) is the mass of the solute and \(V\) is the volume of the solvent. Substituting \(m = 9.02\ g\) and \(V=100\ mL\) into the formula, we get \(S=\frac{9.02\ g}{100\ mL}=0.0902\ g/mL\).

Answer:

\(0.0902\ g/mL\)