Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Calculate the mass of sodium chloride:
Problem:
Let us calculate the mass of sodium chloride in a solution containing 24Na (half-life, 15 h) whose activity is 5.7 mCi.
Suppose w be the weight of 24Na present in sodium chloride
Answer:
We know that λ = 0.693/t1/ 2 = 0.693/15 × 60 × 60s-1
Rate of disintegration - dN/dt = λ N = (0.693 /15 × 3600) × (m × 6.02 × 1023/24)
= 3.219 w×1017 disintegrations per sec
Given that
Activity = -dN/dt = 5.7 × 3.7 × 10 7 = 3.219 m × 1017
... m = 6.55 ×10 -10 g. or 0.655 ng 24Na in NaCl
... mass. of 24NaCl in solution = 0.655 × 59.5 /24 = 1.62 ng
It may be noted that disintegration per sec. (dps) is frequent referred to as the activity of a radioactive sample and measured as counts per second (cps) or per min (cpm). These are related by ε × (dps) = cps where ε is the efficiency of the detection system. A more useful parameter is specific activity defined as the activity per unit mass of the sample. For most typical radio analytical experiments, only mCi or µCi amounts of radioactivity is used and these weigh insignificantly (ng or pg) small.
#uestion.. what is difference between acetaldehyde and ketone
Completeness of a harmitian operator
Energy difference is maximum between which of the consecutive energy levels in an atom? solution) According to the line spectrum of hydrogen maximum energy is there between FIRST
second objection of kekule struture
When are conditions right for harvesting a crop? When the crop is ready for harvest, will depend largely on weather conditions and the state of the market. When the deci
Principal quantum number of an atom represents : (1) Size of the orbital (2) Spin angular momentum (3) Orbital angular momentum (4) Space orientation of the orbital
Geometrical or cis-trans isomerism The compounds that have similar molecular formula but differ in the relative spatial arrangement of atoms or groups in space are termed a
How can we get assignment and earn money,?
In the formation of Nacl from Na and cl: (1) Sodium and chlorine both give electrons (2) Sodium and chlorine both accept electrons (3) Sodium loses electron and chlori
A 10L helium balloon at a pressure of two bar at 27C. Some O 2 is now inside in balloon and final volume is made 30L. the pressure also fell to 1 bar at similar temperature. the p
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd