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~angel~
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I'm just having some trouble answering a few of these questions.
1.Calculate the molar activity of 3H (tritium) (in curie), given it's half life is 12.26 years.
My calculations=
T(1/2) = ln2/Y (where Y=decay rate)
Y=ln2/(12.26*365*24*60*60) = 1.79*10^-9
Molar activity= Y*6.022*10^23 = 1.08*10^15
In curie = (1.08*10^15)/(3.70*10^10)
= 2.92*10^4 curie
The answer according to the solutions is 2.916*10^3 curie/mol. I'm pretty sure I'm right, but I just wanted to get it checked. The question states its meant to be answered in curie, not curie/mol anyway.
2. The energy associated with one photon of light when an electron drops from it's first excited state back to it's ground state is 3.37*10^-19 J.
The ionisation energy of ground state sodium is 8.34*10^-19 J per atom. Calculate the energy required to ionise the 3p electron of an excited sodium atom. Give your answer in kJ/mol.
3. A saturated solution of iodine in water contains 0.330g I2 per litre, but more than this amount can dissolve in a potassium iodide soltion because of the following equilibrium.
I-(aq) + I2(aq) <---> I3-(aq)
A 0.100 M KI solution dissolves 12.5g of I2 per litre, most of which is converted to I3-(aq). Assuming that the concentration of I2(aq) in all saturated solutions is the same, calculate the equilibrium constant for the above reaction.
Any help would be appreciated.
Thanks.
1.Calculate the molar activity of 3H (tritium) (in curie), given it's half life is 12.26 years.
My calculations=
T(1/2) = ln2/Y (where Y=decay rate)
Y=ln2/(12.26*365*24*60*60) = 1.79*10^-9
Molar activity= Y*6.022*10^23 = 1.08*10^15
In curie = (1.08*10^15)/(3.70*10^10)
= 2.92*10^4 curie
The answer according to the solutions is 2.916*10^3 curie/mol. I'm pretty sure I'm right, but I just wanted to get it checked. The question states its meant to be answered in curie, not curie/mol anyway.
2. The energy associated with one photon of light when an electron drops from it's first excited state back to it's ground state is 3.37*10^-19 J.
The ionisation energy of ground state sodium is 8.34*10^-19 J per atom. Calculate the energy required to ionise the 3p electron of an excited sodium atom. Give your answer in kJ/mol.
3. A saturated solution of iodine in water contains 0.330g I2 per litre, but more than this amount can dissolve in a potassium iodide soltion because of the following equilibrium.
I-(aq) + I2(aq) <---> I3-(aq)
A 0.100 M KI solution dissolves 12.5g of I2 per litre, most of which is converted to I3-(aq). Assuming that the concentration of I2(aq) in all saturated solutions is the same, calculate the equilibrium constant for the above reaction.
Any help would be appreciated.
Thanks.