Answer
B. One element takes the place of another in a compound
Explanation
A single-replacement reaction occurs when one element is substituted for another element in a compound.The reacting materials are normally pure elements such as a metal or hydrogen gas with an aqueous compound.A new aqueous compound plus a different pure element are formed as products.
The increase of the boling point of a solution is a colligative property.
The formula for the increase of the normal boiling point of water is:
ΔTb = Kb * m
Where m is the molallity of the solution and Kb is the molal boiling constant in °C/mol.
ΔTb = 0.51 °C / m * 0.100 m = 0.051 °C.
So, the new boiling temperature is Tb = 100°C + 0.051°C = 100.051 °C.
Answer: 100.051 °C
The molecule BH3 is trigonal planar, with B in the center and H in the three vertices. Ther are no free electrons. All the valence electrons are paired in and forming bonds.
There are four kind of intermolecular attractions: ionic, hydrogen bonds, polar and dispersion forces.
B and H have very similar electronegativities, Boron's electronegativity is 2.0 and Hydrogen's electronegativity is 2.0.
The basis of ionic compounds are ions and the basis of polar compounds are dipoles.
The very similar electronegativities means that B and H will not form either ions or dipoles. So, that discards the possibility of finding ionic or polar interactions.
Regarding, hydrogen bonds, that only happens when hydrogen bonds to O, N or F atoms. This is not the case, so you are sure that there are not hydrogen bonds.
When this is the case, the only intermolecular force is dispersion interaction, which present in all molecules.
Then, the answer is dispersion interaction.
It is like an idea that they come up with in an experimeant
Answer:
What is the question? I don't understand what you are trying to say.