Question

PEG 400 is a liquid with a specific gravity of 1.13. What volume should be measured for the preparation?

Answer 1

Answer:

354 cm³

Explanation:

Step 1: calculate the density of PEG 400

$Specific gravity({\gamma}) = \frac{density of liquid (\rho _{l})}{density of water (\rho_{w})}$

$1.13=\frac{\rho _{l}}{1(\frac{g}{m^3})}$

${\rho _{l}$ = 1.13X1 = 1.13 $\frac{g}{cm^3}$

Step 2:

Molecular weight of PEG 400 = 400g/mol

Step 3: calculate the volume of PEG 400 to be measured

$Volume _{PEG 400} =\frac{mass of _{PEG 400}}{density of _{PEG 400}}$

$Volume _{PEG 400}=\frac{400}{1.13}(cm^3)$

                                       = 353.98 cm³

                                       ≅354 cm³