[kls6677]

5.  undergoes spontaneous decay forming an alpha particle and . If the decay of one mole of  releases , calculate the amount of mass lost ( ) in the decomposition of one mole of .  2.0
  A.   
  B.   
  C.   
  D.   
  E.   
 
6.  is one of the many radioactive byproducts of nuclear power plants.  decays by beta emission with a half-life of 30.0 years. How many years will be required for a sample of  to decay to 1% of its original activity?  2.0
  A. 3000 years 
  B. 231 years 
  C. 199 years 
  D. 65 years 
  E. 47 years 
 
7. The oxidation numbers for the metals potassium and cobalt in the compound  are, respectively  2.0
  A. +1 and +2 
  B. +1 nad +3 
  C. +1 and +4 
  D. +3 and +1 
  E. +2 and +1 
 
8. Which response gives the correct coordination number (C.N) and oxidation number (O.N) of the transition metal atom in ?  2.0
  A. C.N =2; O.N=+3 
  B. C.N =3; O.N=+1 
  C. C.N =4; O.N=+2 
  D. C.N =6; O.N=+3 
  E. C.N =6; O.N=+2 
 

[Alberto_Kravina]

Show us your attempts! We're NOT here to do your homework!

Well, a hint for #6: It is an exponential decay Formula: N(t)=N(0)*e^(-c*t)

c=ln(2)/T_1/2

[Borek]

Read forum rules.

You have been warned.

[jdurg]

This thread has been locked as we will not allow anybody to foolishly post the answers to your homework.