Question

A chemistry student needs 50.0 g of glycerol for an experiment. By consulting the CRC Handbook of Chemistry and Physics, the student discovers that thedensity of glycerol is 1.26 g•cm^-3. Calculate the volume of glycerol the student should pour out.Be sure your answer has the correct number of significant digits.

Answer 1

In order to find the volume of glycerol the student should pour out, we need to know the relation between its mass M, its volume V, and its density d:

V = M/d

Now, observe that:

M = 50.0 g

d = 1.26 g * cm-³ (this means each cubic centimeter of the substance contains 1.26 g)

Then, we can use those values in the formula for the volume:

`V=(50.0g)/(1.26g\cdot cm^(-3))=(50.0)/(1.26)cm^3\cong39.68cm^3`

Notice that the number of significant figures of each given measure is 3 (the zero after the dot in 50.0 also counts as a significant figure).

Therefore, the answer with the correct number of significant figures is:

39.7 cm³