Answer:
25% thorium will left after 50 days.
Explanation:
Half life:
A nuclear half is the time period of radioactive material in which its amount remain halved.
In given question it is stated that the half life thorium-234 is 25 days. Which means after passing the 25 days the amount of thorium must be halved of original amount.
For example,
If the original concentration was 100%, than after 25 days it will be 50%.
After 50 days amount of thorium left:
Number of half life = T (elapsed) / T half life
Number of half life = 50/25
Number of half life = 2
At first half life amount of thorium left = 100/2 = 50
After second half life amount of thorium left = 50/2 = 25
Total amount decayed = 50+25 = 75
Amount left after 50 days = 100-75 = 25
25% thorium will left after 50 days.
A. Archilles ! Hope this helped :)!
248.72 g/mol
CuSO4 has a molar mass of 159.62. H2O has a molar mass of 18.02, which is multiplied by 5 to reflect the 5 H2O molecules.
159.62+5(18.02)=249.72 g/mol
The volume of Helium gas needed for storage is 2.00 L (answer C)
<u><em> calculation</em></u>
The volume of Helium is calculated using ideal gas equation
That is Pv =nRT
where;
P( pressure) = 203 KPa
V(volume)=?
n(number of moles) = 0.122 moles
R(gas constant) = 8.314 L.Kpa/mol.K
T(temperature)= 401 K
make V the subject of the formula by diving both side by P
V=nRT/p
V={[0.122 moles x 8.314 L. KPa/mol.K x 401 K] / 203 KPa} = 2.00 L
Answer:
I dont lnow much about chemistry, but I believe it's either d or a. sorry if its wrong!