Answer : Option B) All collisions between particles are perfectly elastic.
Explanation : Gases consits of molecules which are compressible because the gas particles which have a small volume compared to the container.
The collisions are perfectly elastic because when gases are left alone in a container they don't seem to lose energy and do not spontaneously get converted into a liquid, also energy is not lost during collisions.
In the diagram given above one can interpret that the gaseous molecules are in random motion inside the container and when they collide with other molecule of gas they do not lose energy. Therefore, this shows perfectly elastic collisions.
Answer:
semipermeability
Explanation:
partially but not freely or wholly permeable specifically : permeable to some usually small molecules but not to other usually larger particles a semipermeable membrane.
Answer:
1024Å
Explanation:
The Rydberg equation is an empirical relationship equation expressed by Balmer and Rydberg which is given as:
1/λ =
.............................(1)
where
is the Rydberg constant given as
, n is the transition level and the subscript f and i show the final and initial level numbers respectively. λ is the wavelength.
= 1

Using equation (1), we have
1/λ 
= 
= 
= 
= - 9763300
λ = 
= 
We should note that the negative sign we have is as a result of photon absorption whereby the hydrogen atom gains energy to undergo a transition from the lower energy level to a higher one. Wavelength does not have a negative value.
To convert to Å, we have
λ =
= 1024Å
Therefore the wavelength of the photon in Å is 1024Å
If we remove 2 electrons, the new charge will be positive by 2 units. Hence, the ion is

.