Question

Suppose a laboratory has a 38 g sample of polonium-210. The half-life of polonium-210 is about 138 days. How many half-lives of polonium-210 occur in 1104 days? How much polonium is in the sample 1104 days later?

Answer 1

\[m_0\cdot \left(\frac{1}{2}\right)^\frac{t}{t_{1/2}}=m_t \\
38 \cdot \left(\frac{1}{2}\right)^\frac{1104}{138}=m_{t} \\
m_{t}=38\left(\frac{1}{2}\right)^8=\frac{38}{256}=0.1484
\]

Answer 2

so 8 ; 0.15 g?

Answer 3

you round up ?

Answer 4

I dont think so.

Answer 5

0.1484375

Answer 6

answers are:
9 ; 0.07 g
8 ; 2,2622 g
8 ; 4.75 g
8 ; 0.15 g

Answer 7

8 ; 0.15 g rounding up then