Elements are substances that contain only 1 kind of atom.
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.
Answer:
The answer to your question is pH = 1.45
Explanation:
Data
pH = ?
Volume 1 = 200 ml
[HCl] 1 = 0.025 M
Volume 2 = 150 ml
[HCl] 2 = 0.050 M
Process
1.- Calculate the number of moles of each solution
Solution 1
Molarity = moles / volume
-Solve for moles
moles = 0.025 x 0.2
result
moles = 0.005
Solution 2
moles = 0.050 x 0.15
-result
moles = 0.0075
2.- Sum up the number of moles
Total moles = 0.005 + 0.0075
= 0.0125
3.- Sum up the volume
total volume = 200 + 150
350 ml or 0.35 l
4.- Calculate the final concentration
Molarity = 0.0125 / 0.35
= 0.0357
5.- Calculate the pH
pH = -log [H⁺]
-Substitution
pH = -log[0.0357]
-Result
pH = 1.45
First off chlorine is not a metal so you can ignore that one.
Sodium and Rubidium are in group 1 of the periodic table and Magnesium is in group 2.
Group one metals are more reactive than group two because it is harder for the group two metals to lose their 2 valence (outer most) electrons.
As you go down group 1 there is an increase in the reactivity this is because as you go down there is an increase in the atomic radius which leads to more shielding. This weakens the electrostatic forces of attraction making it easier to lose the outermost electrons, therefore they are more reactive.
Answer:
Both molarity and formality express concentration as moles of solute per liter of solution. Formality is a substance's total concentration in solution without regard to its specific chemical form. ... The formality of a solution is defined as the number of formula mass of any solute dissolved in 1 litre of solution.
