Answer:
Ethos, because she is using her own knowledge as a tool.
Explanation:
Harriet Tubman was an activist and served as a spy for Union Army. <u>'Harriet Tubman: Conductor on the Underground Railroad'</u> is a book written by Ann Petry narrating the accounts of life of Harriet Tubman who helped free 300 slaves using the paths of Underground Railroad.
In the given excerpt, Tubman has used the rhetorical appeal of 'ethos' as she is using her own knowledge as a tool. While rescuing slaves using Underground Railroad, Tubman made up several stories to keep the slaves moving and encourage them in their paths of freedom. The path for freedom was dangerous, and Tubman knew that some may back up from this, so she kept telling them about people who chose to struggle for freedom, made up stories about them and used this knowledge as a tool to keep the slaves encouraged and motivated. And no one asked her even one question as they trusted her (credibility-- element of ethos).
Thus, the tool Tubman has used in the given excerpt is ethos.
The enthalpy of fusion for Hg is 2.29 kJ/mol. 0.89 kJ is the energy change when 78.0 g of Hg melts at −38.8°C.
<h3>What is Enthalpy of Fusion ?</h3>
The amount of energy needed to change 1 mole of substance under state change at constant temperature and pressure is called enthalpy of fusion. It is also known as Latent heat of fusion. Unit of enthalpy of fusion is kJ/mol.
<h3>How to find the change in energy ? </h3>
To find the change in energy use this expression:
q = n ΔH
where
q = Energy change
n = number of moles
ΔH = Molar enthalpy
Number of moles (n) = 
= 
= 0.39 mol
Now put the values in above formula we get
q = n ΔH
= 0.39 mol × 2.29 kJ/mol
= 0.89 kJ
Thus from the above conclusion we can say that The enthalpy of fusion for Hg is 2.29 kJ/mol. 0.89 kJ is the energy change when 78.0 g of Hg melts at −38.8°C.
Learn more about the Latent heat of fusion here: brainly.com/question/87248
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Answer:
is a well-sustantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.such fact- supported theories are not "guesses" but reliable accounts of the real worlds.
Answer:-3463 kJ and -3452kJ
Explanation:
ΔU is the change in internal energy of a system and its formula is;
ΔU = q + w
Where q represents heat transferred into or out of the system. Its value is positive when heat is transfer into the system and negative when heat is produced by the system.
W represents the work done on or by the system. Its value is positive when work is done on the system and negative when it is done by the system.
For the system in this question, we see that it produces heat which means heat is transferred out of the system, therefore the value of q is negative, it can also be seen that work is done by the system which means that w is also negative.
Therefore,
ΔU = -q-w
ΔU = -3452 kJ – 11kJ
= - 3463kJ
ΔH is the change in the enthalpy of a system and its formuls is;
ΔH = ΔU + Δ(PV)
By product rule Δ(PV) becomes ΔPV + PΔV
At constant pressure ΔP = 0. Therefore,
ΔH = -q-w + PΔV
w is equals to PΔV, So:
ΔH = -q
ΔH = -3452kJ
