Answer:
The answer to your question is 25 grams
Explanation:
Data
half-life = 5730 years
sample = 200 g
after 3 half-lives
Process
Calculate the amount of sample after one, two and three half-lives.
After each half-life, that of sample is half the previous amount.
Number of half-lives Amount of sample
0 200 g
1 100 g
2 50 g
3 25 g
M(NH₃)=51g, n(NH₃)=m/M=51g÷17g/mol(14+3×1)=3mol
N(NH₃)=n×Na(Avogadro number)=3mol×6·10²³1/mol=18×10²³ molecules
Often, the rock layers bookending the mass extinction are noticeably different in their compositions. These changes in the rocks show the effects of environmental disturbances that triggered the mass extinction and sometimes hint at the catastrophic cause of the extinction
Answer:
The concentration is 
Explanation:
From the question we are told that
The absorbance is 
The length is 
Generally absorbance is mathematically represented as
where 
is the molar absorptivity of FeSCN2 with a value 
and 
is the equilibrium concentration of FeSCN2
So
substituting values
