Answer:

Explanation:
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In this case, according to the given chemical reaction, it possible for us to set up the expression for the calculation of the enthalpy change as shown below:

Thus, given the values of the enthalpies of formation on the attached file, we obtain:
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Answer: c. elements in the same row of the periodic table
Explanation: It kind of represents a graph of the periodic table
Answer:

Explanation:
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In this case, since the density is defined as the ratio of the mass and volume:

We can compute the mass of blood as follows:

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The average atomic mass of her sample is 114.54 amu
Let the 1st isotope be A
Let the 2nd isotope be B
From the question given above, the following data were obtained:
- Abundance of isotope A (A%) = 59.34%
- Mass of isotope A = 113.6459 amu
- Mass of isotope B = 115.8488 amu
- Abundance of isotope B (B%) = 100 – 59.34 = 40.66%
- Average atomic mass =?
The average atomic mass of the sample can be obtained as follow:

Thus, the average atomic mass of the sample is 114.54 amu
Learn more about isotope: brainly.com/question/25868336