A certain acid has a density of 0.92 g/cm^3. If a monolayer of the acid is formed on the surface of water on a 5.25 cm diameter watch glass; what is the mass of the acid of the monolayer?

Base area of the monolayer?

Volume of monolayer?

Mass of acid of monolayer

Respuesta :

Explanation:

The given data is as follows.

          Length of molecule = [tex]11^{o}A[/tex] = [tex]11 \times 10^{-8} cm[/tex]

(as 1 cm = [tex]10^{8}^{o}A[/tex])

           Density = 0.92 [tex]g/cm^{3}[/tex]

          Diameter of watch glass = 5.25 cm

Hence, radius will be calculated as follows.

                 r = [tex]\frac{5.25}{2}[/tex]

                   = 2.625 cm

(a) Now, we will calculate the area of watch glass as follows.

              Area = [tex]\pi r^{2}[/tex]

                       = [tex]3.14 \times (2.625)^{2}[/tex]

                       = [tex]3.14 \times 6.8906[/tex]

                       = 21.636 [tex]cm^{2}[/tex]

Minimum thickness of molecule will be used for the formation of monolayer.

Thickness of layer = length of molecule = [tex]11 A^{o}[/tex]

(b) Now, we will calculate the volume of monolayer as follows.

           Volume = Area × Length

                         = [tex]21.636 cm^{2} \times 11 \times 10^{-8}[/tex]

                         = [tex]238 \times 10^{-8} cm^{3}[/tex]

Hence, volume of the monolayer is [tex]238 \times 10^{-8} cm^{3}[/tex].

(c)  Mass of monolayer will be calculated as follows.

        Mass of monolayer = volume × density

                                         = [tex]238 \times 10^{-8} cm^{3} \times 0.92[/tex]

                                         = [tex]218.96 \times 10^{-8} g[/tex]

                                         = [tex]2.18 \times 10^{-6} g[/tex]

Hence, the mass of monolayer is [tex]2.18 \times 10^{-6} g[/tex].