Answer: half life
Explanation: Radioactive decay follows first order kinetics and the time required for the decay of a radioactive material is calculated as follows:
t= time required
k= disintegration constant
x= amount of substance left after time t
a= initial amount of substance
when one half of the sample is decayed, one half of the sample remains and t can be represented as 
at 
, 
Answer:
Given : No. Of moles = 1.5
To calculate : no. Of molecules =N
We know that moles = N / 6.022 x 10²³
Therefore, 1.5 x 6.022 x 10²³ = N
Hence N = 9.0330x 10²³ molecules
Answer:
The total number of orbitals for a given n value is n2.
Explanation:
For a hydrogen atom with n=1, the electron is in its ground state; if the electron is in the n=2 orbital, it is in an excited state.
Fhicifhyfcifyfjfhdjgfcgufhhdhgddtrd
