The answer is London dispersin forces and dipole-induced dipole forces.
The London dispersion force is a temporary attractive force that results
when the electrons in two adjacent atoms occupy positions that make the
atoms form temporary dipoles. This force is sometimes called an induced
dipole-induced dipole attraction. This force is found in any compound and is the weakest atraction force between atoms or molecules.
Those temporay dipoles are not like the dipoles that form the polar molecules, because the polar molecules are the result of permanent dipoles.
"The boron-nitrogen interaction in the studied molecules shows some similarities with the N→B bond in the H3N-BH3 molecule, formally understood as covalent-dative. ... The results show that all the studied BN bonds are triple, since three two-center orbitals have been obtained."
"Formation of a dative bond or coordinate bond between ammonia and boron trifluoride. When the nitrogen donates a pair of electrons to share with the boron, the boron gains an octet. ... In addition, a pair of non-bonding electrons becomes bonding; they are delocalized over two atoms and become lower in energy."
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 is: <span>he boiling point of a 1.5 m aqueous solution of fructose is </span>100.7725°C.
The boiling point
elevation is directly proportional to the molality of the solution
according to the equation: ΔTb = Kb · b.<span>
ΔTb - the boiling point
elevation.
Kb - the ebullioscopic
constant. of water.
b - molality of the solution.
Kb = 0.515</span>°C/m.
b = 1.5 m.
ΔTb = 0.515°C/m · 1.5 m.
ΔTb = 0.7725°C.
Tb(solution) = Tb(water) + ΔTb.
Tb(solution) = 100°C + 0.7725°C = 100.7725°C.
