Organic Chemistry- Substances only found in living organisms.
Physical Chemistry- Structure of physical compounds and the amount of energy they have.
Inorganic Chemistry- Study of carbon containing compounds.
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
Density = mass/volume
D = 40/80 = 0.5g
D= 0.5g
Answer:
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