Answer:
Ksp = [La3+]2[CO32–]3.
Explanation:
Assume the CaCI2 dissolves completely in the water.. The density of water at 25.0°C is 0.997 g/L, and the KF of H20 is 1.858°C kg/mol.
Answer:
-4741 °C
Something is strange, because this is a weird number.
Explanation:
ΔT = Kf . m. i
That's the colligative property of freezing point depression.
Kf = Cyroscopic constant
m = molality (moles of solute in 1kg of solvent)
i = Van't Hoff factor (numbers of ions dissolved)
We assume 100% dissociation:
CaCl₂ → Ca²⁺ + 2Cl⁻ i = 3
ΔT = Freezing point of pure solvent - Freezing point of solution
Let's determine molality
Solute = CaCl₂
Moles of solute = 23.5 g . 1 mol/ 110.98 g = 0.212 moles
We determine the mass of solvent by density. Density's data is in g/L. We need to convert the volume from mL to L
250 mL . 1L / 1000 mL = 0.250 L
0.997 g/L = mass of water / volume of water → 0.997 g/L . volume of water = mass of water
0.997 g/L . 0.250L = 0.249 g
Now, we convert the mass of water from g to kg
0.249 g . 1 kg / 1000 g = 2.49×10⁻⁴ kg
Molality = mol/kg → 0.212 mol / 2.49×10⁻⁴ kg = 850.5 m
We replace data:
0°C - Freezing point of solution = 1.858 °C . kg /mol . 850.5 mol/kg . 3
Freezing point of solution = -4741 °C
Answer:
The freezing point of the solution is -4.74 °C
Explanation:
Step 1: data given
Mass of calcium chloride CaCl2 = 23.50 grams
Step 2: Calculate moles CaCl2
Moles CaCl2 = mass CaCl2 / molar mass CaCl2
Moles CaCl2 = 23.50 grams / 110.98 g/mol
Moles CaCl2 = 0.212 moles
Step 3: Calculate mass H2O
Density = mass / volume
Mass = density * volume
Mass H2O = 997 g/L * 0.250 L
MAss H2O = 249.25 grams
Step 3: calculate molality of the solution
Molality = moles CaCl2 / mass H2O
Molality = 0.212 moles / 0.24925 kg
Molality = 0.851 molal
ΔT = i*Kf*m
⇒with ΔT = the freezing point depression = TO BE DETERMNED
⇒ with i = the van't Hoff factor = 3
⇒with Kf = the freezing point depression constant of water = 1.858 °C /m
⇒with m = the molality = moles CaCl2 / mass water = 0.851 molal
ΔT = 3 * 1.858 * 0.851
ΔT = 4.74 °C
Step 4: Calculate the freezing point of the solution
ΔT = T (pure solvent) − T (solution)
ΔT = 0°C - 4.74 °C
The freezing point of the solution is -4.74 °C
NOTE: the density of water = 0.997 kg/L or 997 g/L
(2) 40. mL at 80.°C (4) 80. mL at 40.°C
A. they remain level since densities in both plates are equal.
B. they both push back down into the mantle
C. one plate rides over the other one and forms a trench
D.they buckle upward and form mountains
Answer:
D. They buckle upward and form mountains.
Explanation:
When two plates (either oceanic or terrestrial) converge and they are of similar density then they will crash into each other and form mountains. A great example of this is when India crashed into the Asian continent and the Himalayas were formed.