Explanation :
In thermodynamics, a system is region or part of space which is being studied and observed while the surrounding is the region or space around the system which interacts with the system.
Here in the experiment ,system which is observed is reaction or changes when citric acid and sodium bicarbonate are mixed together. And the mixing is carried out in the calorimeter which serves as a surrounding around the system.
The reason behind the using the calorimeter is measure the energy change occurring during the reaction.
So technicaly the answer is D
Answer:
- <u>b. three half-lives</u>
Explanation:
The number of half-lives elapsed, n, is calculated dividing the time by the half-life time:
- n = time / half-life time
<u>a. A sample of Ce-141 with a half-life of 32.5 days after 32.5 days</u>
- n = 32.5 days / 32.5 days = 1 half-life
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<u>b. A sample of F-18 with a half-life of 110 min after 330 min</u>
- n = 330 min / 110 min = 3 half-lives
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<u>c. A sample of Au-198 with a half-life of 2.7 days after 5.4 days</u>
- n = 5.4 days / 2.7 days = 2 half-lives
Before we get into the calculation, there are several things that we need to pay attention to:
- There are 6 moles of C
- The carbon mass of a glucose is 180.15 g
So,
<span>#30.5g Glucose(1 mol of glucose/180.15g Glucose)=.169 mol glucose
</span><span>#169 mol glucose(6 Moles of C/1mol C6H12O6) =1.014 mol of C
</span>#<span>1.014 Mol C(6.022x10^23 atoms/ 1 Mol) = 6.11 X 10^23 Atoms of C</span>
