Answer:
B. the atomic weight of the element
Explanation:
since it talks about mass i think weight
The first example of diffusion is smoking a cigarette when u light it it spreads through the air.
The second example is lighting a candle in a room it the smoke spreads through the air.
Smoke can be very bad for the air and the people around because it can cause many problems with your breathing.
Answer:
Isotope, one of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behaviour but with different atomic masses and physical properties.
When multiplying and deviding follow the least number of sf.
since wavelength = 1/period
hence wavelength=1/2.7
=0.37 (2sf)