Answer:
ΔHrxn = 178.3 kJ/mol
Explanation:
Using Hess's law, you can obtain ΔHrxn from ΔHf of products and reactants, thus:
<em>Hess's law: </em>
ΔHrxn = <em>∑nΔHf products - ∑nΔHf reactants</em>
<em>Where n are moles of reaction</em>
<em> </em>
Thus, from the reaction:
CaCO₃(s) → CaO(s) + CO₂(g)
ΔHrxn = <em>ΔHf </em>CaO(s)<em> + ΔHf </em>CO₂(g)<em> - ΔHf </em>CaCO₃(s)
ΔHrxn = -635.1kJ/mol + (-393.5kJ/mol) - (-1206.9kJ/mol)
<em>ΔHrxn = 178.3 kJ/mol</em>
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.
Answer:
Through the processes of melting of the glacier to form water, evaporation of water, condensation and precipitation, water in the form of melting glaciers in Greenland could have moved to the Loch Raven Reservoir and on to our school's water fountain.
Explanation:
Considering a glacier in Greenland. When this glacier melts, its waters flows into the ocean. Subsequent heating of the ocean by sun causes the water to evaporate and rise into the sky as water vapor. This water vapor cools on rising and then condenses into water droplets in sky which forming clouds. A cloud is made of water drops or ice crystals floating in the sky.
Wind movement would then carry the clouds over great distances. These water droplets within a cloud will condense onto one another, causing the droplets to grow. When these water droplets become too heavy to remain suspended in the cloud, they will then either precipitate as rain or snow on land, rivers and oceans.
Over time, with continuous cycling and repetition of these processes, water melting from a glacier in Greenland will eventually make its way into the Big Gunpowder Falls river which feeds the Loch Raven Reservoir in Baltimore and subsequently, the water will be supplied to our school's water fountain.
Answer: Values of
A = 
B = 
C = 
D = 95pm
E = 1139.9kJ/mol
F = 737.7kJ/mol
G = 495.8kJ/mol
Explanation: We are asked some of the atomic and orbital properties of elements.
Atomic Radii: This is a atomic property of an element which refers to the total distance from the atom's nucleus to the outermost shell. It is usually expressed in 
.
Ionic Radii: This is also a atomic property of an element which refers to the distance between the nucleus of the two gaseous atoms touching each other. It is usually expressed in pm.
First Ionization Energy: This is an orbital property which refers to the energy required to remove one mole of loosely held electron from one mole of gaseous ions. It is usually expressed in kJ/mol.
