Answer:
2.2 °C/m
Explanation:
It seems the question is incomplete. However, this problem has been found in a web search, with values as follow:
" A certain substance X melts at a temperature of -9.9 °C. But if a 350 g sample of X is prepared with 31.8 g of urea (CH₄N₂O) dissolved in it, the sample is found to have a melting point of -13.2°C instead. Calculate the molal freezing point depression constant of X. Round your answer to 2 significant digits. "
So we use the formula for <em>freezing point depression</em>:
In this case, ΔTf = 13.2 - 9.9 = 3.3°C
m is the molality (moles solute/kg solvent)
- 350 g X ⇒ 350/1000 = 0.35 kg X
- 31.8 g Urea ÷ 60 g/mol = 0.53 mol Urea
Molality = 0.53 / 0.35 = 1.51 m
So now we have all the required data to <u>solve for Kf</u>:
Answer:
No
Explanation:
In ideal solutions, the interactions between solute - solvent are approximately the same as those of solute - solute and solvent - solvent, that is the interactions are to be practically indistintiguishable after disolution.
The moment we have a release of energy (the solution feels warm) we are to conclude that there are strong interactions between the water and methanol molecules so we would expect the solution to be non ideal.
The reason for the interactions is the presence of hydrogen bonds between methanol and water.
Among the choices, the only one that can be considered a carnivore is C. Adelie penguin. Adelie penguins are found in the Arctic, and feed on aquatic creatures such as krill, fish, and squid. Krill is a type of crustacean that feeds on phytoplankton, which is at the bottom of the food chain.
Increase in temperature makes the atoms speed up, and decrease in temperature makes the atoms move slower.
