Diffusion coefficient is the proportionality factor D in Fick’s law (see Diffusion) by which the mass of a substance dM diffusing in time dt through the surface dF normal to the diffusion direction is proportional to the concentration gradient grad c of this substance:
dM = −D grad c dF dt.
What is rate of diffusion in chemistry?
Diffusion refers to the process of particles moving from an area of high concentration to one of low concentration. The rate of this movement is a
function of temperature, viscosity of the medium, and the size (mass) of the particles
.
What is the formula for rate of diffusion?
rate(gas A) × √molar mass(gas A) = rate(gas B) × √molar mass(gas B)
This means that the relative rate of diffusion of two gases can be used to determine their relative molecular mass (or molar mass).
What is diffusion chemistry?
Diffusion is
the movement of a substance from an area of high concentration to an area of lower concentration
. Diffusion occurs in liquids and gases when their particles collide randomly and spread out. Diffusion is an important process for living things – it is how substances move in and out of cells.
What is volume diffusion?
Lattice diffusion (also called bulk or volume diffusion) refers
to atomic diffusion within a crystalline lattice
. … Diffusing particles migrate from point vacancy to point vacancy by the rapid, essentially random jumping about (jump diffusion).
Which has the lowest rate of diffusion?
As per Graham’s law, the rate of effusion or diffusion is inversely proportional to the square root of its molar mass. Hence,
the gas with the highest molecular weight diffuses
the slowest when it comes to rate of diffusion and helium is the fastest as it is the lightest.
What are the 3 factors that affect the rate of diffusion?
Several factors affect the rate of diffusion of a solute including
the mass of the solute, the temperature of the environment, the solvent density, and the distance traveled
.
What are examples of diffusion?
- The smell of perfumes/Incense Sticks.
- Opening the Soda/Cold Drinks bottle and the CO
2
diffuses in the air. - Dipping the tea bags in hot water will diffuse the tea in hot water.
- Small dust particles or smoke diffuse into the air and cause air pollution.
What is the rate of diffusion in liquid?
Hence we can conclude the rate of diffusion of liquids is
higher than solids
due to the free movement of molecules and lack of strong force of attraction in liquids but rate of diffusion of liquids is lower than gases as in gases molecules are quite far apart. Hence the correct option is option C.
Which gas has highest diffusion rate?
Consequently, the gas with the least molecular weight effuses the fastest hence,
helium gas
has a higher rate of diffusion compared to nitrogen or oxygen.
What are the 3 types of diffusion?
- (i) Simple diffusion is when ions or molecules diffuse from an area of high concentration to an area of low concentration.
- (ii) In osmosis, the particles moving are water molecules.
What are the 4 types of diffusion?
each group a different type of diffusion (relocation, hierarchical, contagious, or stimulus). Each group should come up with one example of diffusion for each of the four different types of scale:
local, regional, and global
.
What are the characteristics of diffusion?
Diffusion is
the natural tendency of a substance to uniformly spread in another by random movement of its molecules or charged particles
from an area of greater concentration to an area of lower concentration due to their kinetic energy. It is dependent on the concentration gradient.
Does diffusion depend on pressure?
Diffusion is the spontaneous movement of molecules from one region to another due to temperature, pressure, concentration, or other force gradients. …
It is dependent on the temperature and pressure
. The pressure dependence is negligible up to about 20 bar.
What is meant by term diffusion?
Diffusion is defined as
the movement of individual molecules of a substance through a semipermeable barrier from an area of higher concentration to an area of lower concentration
[34].
What is diffusion rate?
The rate of diffusion, dn/dt, is
the change in the number of diffusing molecules inside the cell over time
. Since the net movement of diffusing molecules depends on the concentration gradient, the rate of diffusion is directly proportional to the concentration gradient (dC/dx) across the membrane.