The diffusion coefficient for sodium ions crossing a biological membrane 12nm thick is 1.5 x10-18 m2/s. what flow rate of sodium ions would move across an area 12nm x 12 nm if the concentration difference across the membrane is 0.60 mol/dm3

Explanation:

We are given that

Diffusion coefficient,

Thickness of membrane,

Area,

Concentration differences,

We have to find the flow rate of sodium ions.

Flow rate,

Using the formula

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

6.4 cm (max) - 25 cm (min)