What is the percent by mass of sodium in Na2SO4? total mass of element in compound molar mass of compound Use %Element x 100
Answer:
see explanation below
Explanation:
Question is incomplete, so in picture 1, you have a sample of this question with the missing data.
Now, in general terms, the absorbance of a substance can be calculated using the beer's law which is the following:
A = εlc
Where:
ε: molar absortivity
l: distance of the light in solution
c: concentration of solution
However, in this case, we have a plot line and a equation for this plot, so all we have to do is replace the given data into the equation and solve for x, which is the concentration.
the equation according to the plot is:
A = 15200c - 0.018
So solving for C for an absorbance of 0.25 is:
0.25 = 15200c - 0.018
0.25 + 0.018 = 15200c
0.268 = 15200c
c = 0.268/15200
c = 1.76x10⁻⁵ M
9.184 liters CH2O at STP
I think this is correct. Good luck
Mezoic era began 252m years ago and ended 6.6m years ago.
It was a time of geological and biological transition. During this era the continents began to drift to their present configuration.
3 of the largest mass extinction occurred at this era. One which include the dinosaurs.
I hope this helped. :)