To determine the level of radionuclides present
Answer:
I would go for number 5 . It sounds more logical to me.
Answer:
Rock Y
Explanation:
The rock that is older shall be determined based on the number of half lives it has witnessed. A half life is simply the amount of time required for a sample to decay to half of its original mass.
Rock X
From 100% uranium, it decays to 50% uranium. This means it went through just one half life.
Rock Y
From 100% uranium to 25% uranium
100 --> 50 (first half life)
50 --> 25 (second half life)
This means it wen through 2 half lives.
Rock Y is older than Rock X
Is the following reaction spontaneous at 298 K? Answer by calculating ΔG. H2O(g) + C(s) → CO(g) + H2(g) ΔH = 131.3 kJ/mole ΔS = 134 J/mole˙K
No