Answer: 20 mg Te-99 remains after 12 hours.
Explanation: N(t) = N(0)*(1/2)^(t/t1/2)
N(t) = (80 mg)*(0.5)^(12/6)
N(t) = 20 mg remains after 12 hours
Increase in heat, molecules start to escape and it turns to vapor
Atomic mass Hg = 200.59 u.m.a
200.59 g --------------- 6.02x10²³ atoms
( mass Hg ) ----------- 1.20 x10²² atoms
mass Hg = ( 1.20x10²² ) x 200.59 / 6.02x10²³
mass Hg = 2.407x10²⁴ / 6.02x10²³
= 3.998 g of Hg
hope this helps!
Answer:
The electron configuration for a
Mn3+ ion is [Ar]3d4
Explanation: