Answer:
a). The energy released by the alpha decay of 222 Rn is to 218 Po :
= 5.596 MeV
b).The energy of the alpha particle is 5.5 MeV
c) The recoil energy of Po = 0.096 MeV
Explanation:
The equation for the alpha decay of Rn to Polonium is:
The energy of the decay process can be calculated using:
= Change in the mass
Mass of Po = 218.008965 u
Mass of He = 4.002603 u
Mass of Rn = 222.017576 u
= mass of Po + mass of He - mass of Rn
= 4.002603 + 218.008965-222.017576
= - 0.006008
= -5.596 MeV
<u><em>The negative sign means energy is released during the process.</em></u>
b) The energy of the alpha particle is :
= 5.494 MeV
= 5.5 MeV
c).
Recoil energy: When the parent nucleus is at rest before the decay then , there must be the some recoil of daughter nucleus to conserve the momentum.This is termed as recoil energy.
<u><em>The energy of the recoil polonium atom :</em></u>
The formula for recoil energy is :
<em>The total energy - the kinetic energy</em>
<em>= 5.596 - 5.5 </em>
<em>= 0.096 MeV</em>
The solubility of nitrogen in water at 25 °C= 4.88 x 10⁻⁴ mol/L
<h3>Further explanation</h3>
Given
78% Nitrogen by volume
Required
The solubility of nitrogen in water
Solution
Henry's Law states that the solubility of a gas is proportional to its partial pressure
Can be formulated
S = kH. P.
S = gas solubility, mol / L
kH = Henry constant, mol / L.atm
P = partial gas pressure
In the standard 25 C state, the air pressure is considered to be 1 atm, so the partial pressure of N₂ -nitrogen becomes:
Vn / Vtot = Pn / Ptot
78/100 = Pn / 1
Pn = 0.78 atm
Henry constant for N₂ at 25 °c = 1600 atm/mol.L=6.25.10⁻⁴ mol/L.atm
The solubility :
The difference between a substance and a mixture is that a substance is one of a kind, a material of the same composition throughout, on the contrary, a mixture is one or more different substances brought together and mixed together without changing the nature of each single substance.
One way to test it is to take two substances like sand and table salt. They should each be in granular form and in adequate amount to mix. Neither substance has changed after mixing the two. Even though it may not be easy or convenient to accomplish, each substance could be separated out from the mixture.
When it comes to two substances in lump form, it would not be a mixture when one lump is positioned next to the other lump because there are not enough pieces to combine.
However, there could be a mixture of three substances, like sand, table salt and graphite powder and there could be a mixture with four substances, etc., ad infinitum.
Mixtures are of solid substances in general. On the other hand, one starts referring to solutions when liquids are involved. Gases can be a mixture like for example, air is a mixture with nitrogen, oxygen, argon, etc.
Answer:
The body has levels of organization that build on each other. Cells make up tissues, tissues make up organs, and organs make up organ systems. The function of an organ system depends on the integrated activity of its organs.
