Answer:

Explanation:
Hello there!
In this case, sine the solution of this problem require the application of the Raoult's law, assuming heptane is a nonvolatile solute, so we can write:

Thus, we first calculate the mole fraction of chloroform, by using the given masses and molar masses as shown below:

Therefore, the partial pressure of chloroform turns out to be:

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1.785714286 moles
The number of moles (n) for nitrogen is: [ n=50.0÷28.0 ] = 1.785714286 moles.
To get the concentration of the second solution let us use the following formulae
C1V1=C2V2 where C1 is concentration of first solution and V1 is the volume of solution first solution. on the other hand C2 is the concentration of second solution and V2 is the volume of second solution.
therefore
0.8×2=(2+10)×C2
1.6 =12×C2
1.6/12=C2
C2 = 0.1333mg/mL
Answer:
4.419 g
Explanation:
55 years is 5.5 half lives
200 g * (1/2)^5.5 = 4.419 g