A solution (in this experiment solution of NaNO₃) freezes at a lower temperature than does the pure solvent (deionized water). The higher the
solute concentration (sodium nitrate), freezing point depression of the solution will be greater.
Equation describing the change in freezing point:
ΔT = Kf · b · i.
ΔT - temperature change from pure solvent to solution.
Kf - the molal freezing point depression constant.
b - molality (moles of solute per kilogram of solvent).
i - Van’t Hoff Factor.
First measure freezing point of pure solvent (deionized water). Than make solutions of NaNO₃ with different molality and measure separately their freezing points. Use equation to calculate Kf.
I believe the answer is B??????????? Hope this helps
~Queensupreme
Answer:
Metal
Element: Calcium
Valency: 2
Explanation:
To find the element, let's use the periodic table. (Look below)
We already went past 3 shells, just need the 2 electrons after it.
Just skip to the 4th row and count 2 to the right
We end up at Calcium.
Calcium is a metal and we're also on the alkaline earth metals column.
Calcium will need to lose 2 electrons to reach stability, so the valency is 2.
<u>Answer:</u> The half life of the reaction is 1190.7 seconds
<u>Explanation:</u>
The equation used to calculate rate constant from given half life for first order kinetics:

where,
k = rate constant of the reaction = 
= half life of the reaction = ?
Putting values in above equation, we get:

Hence, the half life of the reaction is 1190.7 seconds
Answer:
B. Atom, molecule, cell, organism
Explanation:
Atoms make up molecules. Molecules make up cells. Cells make up tissue. A number of tissues working together creates an organ. Multiple organs working together creates an organ system. Organ systems working together creates one happy, functioning organism. :)