Answer:
- Aluminium sulfate Al2(SO4)3 dissociates in two aluminium ions and three sulfate ions, therefore, van't Hoff factor is 5 (incorrect).
Explanation:
Hello,
In this case, since the van't Hoff factor is related with the species that result from the ionization of a chemical compound, we can see that that
- Aluminium sulfate Al2(SO4)3 dissociates in two aluminium ions and three sulfate ions, therefore, van't Hoff factor is 5 (incorrect).
- Ammonium nitrate NH4NO3 dissociates in one ammonium ions and one nitrate ion, therefore, van't Hoff factor is 2 (correct).
- Sodium sulfate Na2SO4 dissociates in two sodium ions and one sulfate, therefore, van't Hoff factor is 3 (correct).
- Sucrose is not ionized, therefore, van't Hoff factor is 1 (correct).
Best regards.
Hello!
What is the initial temperature of a gas if the volume changed from 1.00l to 1.10l and the final temperature was determined to be 255 ?
We have the following data:
V1 (initial volume) = 1.00 L
V2 (final volume) = 1.10 L
T1 (initial temperature) = ? (in Kelvin)
T2 (final temperature) = 255 K
According to the Law of Charles and Gay-Lussac in the study of gases, in an isobaric transformation, ie when a mass under pressure maintains its constant pressure, on the other hand, as the volume increases, the temperature increases and, if the volume decreases, the temperature decreases (directly proportional to temperature and volume) . We apply the data to the formula of isobaric transformation (Charles and Gay-Lussac), we will see:
multiply the means by the extremes
Answer:
The initial temperature is approximately 231.8 Kelvin
________________________
Answer:
ΔH°rxn = 54.08 kJ
Explanation:
Let's consider the following equations.
a) ClO(g) + O₃(g) ⇄ Cl(g) + 2 O₂(g) ΔH°rxn = –29.90 kJ
b) 2 O₃(g) ⇄ 3 O₂(g) ΔH°rxn = 24.18 kJ
We have to determine the value of heat of reaction for the following reaction: Cl(g) + O₃(g) ⇄ ClO(g) + O₂(g)
According to Hess's law, the enthalpy change in a chemical reaction is the same whether the reaction takes place in one or in several steps. That means that we can find the enthalpy of a reaction by adding the corresponding steps and adding their enthalpies. According to Lavoisier-Laplace's law, if we reverse a reaction, we also have to reverse the sign of its enthalpy.
Let's reverse equation a) and add it to equation b).
-a) Cl(g) + 2 O₂(g) ⇄ ClO(g) + O₃(g) ΔH°rxn = 29.90 kJ
b) 2 O₃(g) ⇄ 3 O₂(g) ΔH°rxn = 24.18 kJ
-------------------------------------------------------------------------------------------------
Cl(g) + 2 O₂(g) + 2 O₃(g) ⇄ ClO(g) + O₃(g) + 3 O₂(g)
Cl(g) + O₃(g) ⇄ ClO(g) +O₂(g)
ΔH°rxn = 29.90 kJ + 24.18 kJ = 54.08 kJ
The heat of the reaction (ΔH°rxn) for the reaction Cl(g) + O3(g) ? ClO(g) + O2(g) is calculated using Hess's Law. The sum of the heat of reversed first reaction and the second reaction provided is 54.08 kJ.
The chemistry question asks to determine the heat of the reaction for the reaction Cl(g) + O3(g) ? ClO(g) + O2(g). In Hess's Law, the heat of the reaction or ΔH for a reaction can be calculated from the sum of the heats of other reactions that sum to the desired reaction. In this case, we want to reverse the first reaction provided (which changes the sign of ΔH) and add it to the second reaction provided.
So, reversing the first reaction we get: Cl(g) + 2 O2(g) ? ClO(g) + O3(g) ?H°rxn = 29.90 kJ
Adding this to the second reaction: 2 O3(g) ? 3 O2(g), ?H°rxn = 24.18 kJ, gives the reaction Cl(g) + O3(g) ? ClO(g) + O2(g). Adding the ΔH values gives the ΔH for this reaction: 29.90 kJ + 24.18 kJ = 54.08 kJ. So, ?H°rxn for the reaction Cl(g) + O3(g) ? ClO(g) + O2(g) is 54.08 kJ.
#SPJ11
Answer:
1) 108.27 grams of potassium nitarte must be added to 275 mL of water to produce a solution that freezes at -14.5°C.
2) 1.73 is the actual value of the van't Hoff factor, i.
Explanation:
1) Formula used depression in freezing point ;
where,
=Freezing point of solution
T = Freezing point of water
=depression in freezing point =
i = van't Hoff factor of solute
= freezing point constant
m = molality of solution
We have :
of water = 1.86°C/m ,
Molality of solution = m = ?
i = 2
Freezing point of solution =
Freezing point of pure water = T = 0°C
m = 3.898 molal
3.898 moles of potassium nitrate is dissolved in 1 kg of water or 1000 g of water.
Volume of water , V= 275 ml
Mass of water = m
Density of water= d = 1 g/mL
Here, 3.898 moles of potassium nitrate is dissolved in 1 kg of water or 1000 g of water. Then moles of potassium nitarte present in 275 grams of water is :
Mass of 1.072 moles of potassium nitrate :
1.072 mol × 101 g/mol = 108.27 g
108.27 grams of potassium nitarte must be added to 275 mL of water to produce a solution that freezes at -14.5°C.
2) Formula used an Elevation in boiling point;
where,
=boiling point of solution
T = boiling point of water
=Elevation in boiling point =
i = van't Hoff factor of solute
= Boiling point constant
m = molality of solution
of the solution
We have :
of water = 0.512°C/m ,
Molality of solution = m = 3.90 m
i =?
The boiling point of pure water = T = 100.00°C
The boiling point of solution = = 103.45°C
1.73 is the actual value of the van't Hoff factor, i.