Answer:
25 g of an element will remain in the sample.
Explanation:
Initial mass of an element = [tex]N_o = 200 g[/tex]
Final mass of an elemnt after time ,t = N
t = 30 days
Half life of an element =[tex]t_{\frac{1}{2}=10 days[/tex]
[tex]\lambda=\frac{0.693}{t_{\frac{1}{2}}}=\frac{0.693}{10 days}=0.0693 days^{-1}[/tex]
[tex]\log[N]=\log[N_o]-\frac{\lambda t}{2.303}[/tex]
[tex]\log[N]=\log[200 g]-\frac{0.0693 days ^{-1}\times 30 days}{2.303}[/tex]
N = 25.01 49 g ≈ 25 g
25 g of an element will remain in the sample.
