Answer:
13 years
Explanation:
From;
0.693/t1/2 = 2.303/t log (No/N)
Where;
t1/12 = half-life of Cobalt-60 = 5.3 years
t = time taken = the unknown
No = mass of radioactive material originally present = 5.2 g
N = mass of radioactive material at time t = 0.95 g
Substituting values;
0.693/5.3 = 2.303/t log (5.2/0.95)
0.131 = 2.303/t(0.738)
0.131 = 1.6996/t
t = 1.6996/0.131
t = 12.97 years
t = 13 years(to the nearest whole number)
Answer:
Hi the answer should be B or 2
Explanation:
Hope this helps!
Answer:
A. 3.5ml
Explanation:
lowest point of liquid or meniscus
The temperature at which the process be spontaneous is calculated as follows
delta G = delta H -T delta S
let delta G be =0
therefore delta H- T delta s =0
therefore T= delta H/ delta S
convert 31 Kj to J = 31 x1000= 31000 j/mol
T=31000j/mol /93 j/mol.k =333.33K
