a) Calculate the standard reaction entropy for the combustion of methane to carbon dioxide and liquid water at 298 K. b) Calculate the standard reaction entropy for the hydrolysis of liquid water to form oxygen and hydrogen gas. c) Do your results in (a) and (b) agree with the general rule that reaction entropies are positive if there is a net formation of gas in a reaction, and negative if the is a net reduction of gas?
Answer: (a) [tex]\Delta S^{0}[/tex] = - 242.2J/K.mol
(b) [tex]\Delta S^{0}[/tex] = 163.34J/K.mol
(c) Yes
Explanation: Entropy is the measure of randomness or disorder of a system. Standard Entropy has the symbol [tex]S^{0}[/tex].
Mathematically, Entropy is defined as
[tex]\Delta S^{0}=\Sigma S^{0}(products)-\Sigma S^{0}(reagents)[/tex]
Each substance has its own entropy value.
(a) Combustion of Methane:
[tex]CH_{4}+2O_{2}[/tex] ⇒ [tex]CO_{2}+2H_{2}O[/tex]
Using standard entropy table, entropy will be:
[tex]\Sigma S^{0}(products)=214+2(69.91)[/tex] = 353.8
[tex]\Sigma S^{0}=186.264+2(205.138)[/tex] = 596.54
[tex]\Delta S^{0}=[/tex] 353.8 - 596.54
[tex]\Delta S^{0}=[/tex] - 242.2
Standard Entropy for combustion of methane is [tex]\Delta S^{0}=[/tex] - 242.2 J/K.mol.
(b) Hydrolysis of Water:
[tex]H_{2}O_{(l)}[/tex] ⇒ [tex]H_{2}_{(g)}+1/2O_{2}_{(g)}[/tex]
[tex]\Sigma S^{0}(products)=130.684+0.5(205.138)[/tex] = 233.253
[tex]\Sigma S^{0}(reagents)=69.91[/tex]
[tex]\Delta S^{0}=[/tex] 233.253 - 69.91
[tex]\Delta S^{0}=[/tex] +163.34
Standard Entropy for hydrolysis of water is [tex]\Delta S^{0}=[/tex] + 163.34 J/K.mol
(c) Yes, the results prove the general rule: Reactions Entropies are positive for net formation of gas and negative for net reduction of gas. This happens because, as entropy is the measure of disorder, the entropy for gases are greater than for liquids and solids. So, when there is formation of a gas, Entropy increases and when there isn't, entropy decreases.
A silver bar has a mass of 368g. What is the volume in cm³ of the bar? The density of silver is 19.5g/cm³.
Answer:
18.87 cm³Explanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\[/tex]
From the question we have
[tex]volume = \frac{368}{19.5} \\ = 18.871794..[/tex]
We have the final answer as
18.87 cm³Hope this helps you
ASAP PLZ HELP I WILL MARK BRAINLIEST Based on the diagram, what can you conclude about the pole of the magnet? O It is a south pole because the field lines spread out from this end. O It is a north pole because the field lines spread out from this end, O It is a south pole because the field lines enter the magnet at this end. O It is a north pole because the field lines enter the magnet at this end.
Answer:C
Explanation:I took the test
Answer:
It is a south pole because the field lines enter the magnet at this end.
Explanation:
Based on the chemical equation, use the drop-down menu to choose the coefficients that will balance the chemical equation:
(
)BaO2 + (
)H2SO4 → (
)H2O2 + (
)BaSO4
Answer:
1
1
1
1
Explanation:
the equation is balancing
hydrogen sulphide and water molecules have the same shape. however the bond angle in water is greater than the bond angle in hydrogen sulphide. explain this
Answer:
Oxygen is more electronegative than sulphur
Explanation:
Bond angle of a molecule is related to the electronegativity of the central atom. The more electronegative the central atom is, the greater the bond angle.
As electronegativity of the central atom increases, the magnitude of bond pair- bond pair repulsion increases leading to increase in bond angle.
Hence, oxygen, being more electronegative than sulphur asserts a greater bond pair- bond pair repulsion leading to a greater bond angle in water.
1) Compounds Y and Z both have the formula C9H18.
Both Y and Z react with one molar equivalent of hydrogen in the presence of a palladium catalyst to form 2-methyloctane.
The heat of hydrogenation of Y is less than that of Z.
Y and Z each undergo hydroboration/oxidation to give a primary alcohol (OH attached to a primary carbon).
What is the structure of Y?
2) Compound X has the formula C8H12.
X reacts with two molar equivalents of hydrogen in the presence of a palladium catalyst to form cyclooctane.
Treatment of X with ozone followed by zinc in aqueous acid gives two molar equivalents of the same dialdehyde.
What is the structure of X
Answer:
See explanation and images attached
Explanation:
We know that the cis isomer has more heat of hydrogenation since it is less stable than the trans isomer. Since the hydrogenation of both compounds yields the same product and the hydroboration/oxidation both give a primary alcohol, they are geometric isomers and Y is the trans isomer (Image 2).
For the compound C8H12, the compound in question must be 1,5- cyclooctadiene since two moles of the same aldehyde was obtained after ozonolysis and reaction with two equivalents of hydrogen gives cyclooctane (Image 1).
_______ are characterized by having high melting and boiling points as well as being solid at room temperature
A. Iconic lattices
B. Giant covalent structures of ionic lattices
C. Giant covalent
D. Lone pairs
Answer:
C. Giant covalentGiant covalent are characterized by having high melting and boiling points as well as being solid at room temperature. Hence, option C is correct.
What is a covalent bond?A covalent bond shares one or more pairs of electrons between two atoms.
Giant covalent structure:
Polythene: long chains of atoms that are able to rotate along the bonding axis.
Graphite: layers of (hexagonal) carbon sheets; each individual sheet are rigid (allows no rotation.)
Silicon dioxide: three-dimensional (tetrahedral) network of carbon and oxygen atoms; the entire network is very rigid (allows no rotation.)
Diamond: three-dimensional (tetrahedral) network of carbon atoms and is very rigid.
Hence, giant covalent are characterized by having high melting and boiling points as well as being solid at room temperature.
Learn more about covalent bond here:
brainly.com/question/19382448
#SPJ5
through which filter did water went through faster?
Answer:
The filter that water went through faster is Filter paper
If I Gave A Pig Bacon Would He Eat It ?
What statements are always true about limiting reactants?
Select one or more:
1.The limiting reactant has a lower mass than other reactants.
2.The limiting reactant dictates the amount of product.
3.The limiting reactant is always the same for a given reaction.
4.There will be an excess of other reactants at the end of the reaction.
5.The limiting reactant is completely used up in the reaction.
Answer:
5.The limiting reactant is completely used up in the reaction
Explanation:
The limiting reactant is completely used up in the reaction is the correct answer because a limiting reactant is a reactant in chemical reaction that is completely consumed or used up in the chemical reaction. Limiting reactant when it is completely used up limits the amount of products that will be formed. The reaction will be halted or will stop when the limiting reactant is totally used up.
The statement that is right as regards a limiting reactants in a reaction is 5:.The limiting reactant is completely used up in the reaction.
The limiting reagent can be regarded as a reactant during chemical reaction, which is been consumed totally at the end of the reaction without remains. The amount of product that is formed during a reaction can be limited by action of the limiting reagent this is because once this reagent is used up the reaction cannot proceed again.Therefore, option 5, is correct.
Learn more at:https://brainly.com/question/19031443?referrer=searchResults
OTHER OPTIONS THAT COMPLETE THIS QUESTION ARE:
The limiting reactant has a lower mass than other reactants.
2.The limiting reactant dictates the amount of product.
3.The limiting reactant is always the same for a given reaction.
4.There will be an excess of other reactants at the end of the reaction.
How many grams of NaCl are needed to make 300ml of a 2% solution
Answer:
2grams as per the question
Which statement describes a physical change? *
A. An iron bolt on a bridge rusts and weakens the bridge.
B. The surface of a silver cup turns black when it is exposed to air.
C. A sculptor casts a statue in molten bronze and allows it to harden.
D. Slivers of magnesium in fireworks form a bright glow as they burn.
The statement that describes a physical change is a sculptor casts a statue in molten bronze and allows it to harden. The correct option is C.
What are physical changes?"A physical change is one that simply affects the physical nature of the substance." Usually, increasing the temperature or applying pressure, both, will cause a physical change. In other words, physical changes are reversible.
All the other options like rusting of iron bolts on a bridge is a chemical change when iron reacts with oxygen in the air, it gets rust.
Similarly, silver cups exposed to air react with air is a chemical change, and option d, silver off magnesium that creates light, is also a chemical change.
Thus, the correct option is C. A sculptor casts a statue in molten bronze and allows it to harden.
To learn more about physical changes, refer to the below link:
https://brainly.com/question/21509240
#SPJ2
A common carboxylic acid used in cooking is acetic acid, if its composed of two carbons whats its iupac name
Answer:
ethane
Explanation:
Ethane is an organic chemical compound with chemical formula C ₂H ₆. At standard temperature and pressure, ethane is a colorless, odorless gas. Like many hydrocarbons, ethane is isolated on an industrial scale from natural gas and as a petrochemical by-product of petroleum refining
What is the name of the compound with the formula LiNO3?
Answer:
Lithium nitrate
Explanation:
Lithium nitrate is an inorganic compound with the formula LiNO3. It is the lithium salt of nitric acid (an alkali metal nitrate).
Which of these elements is the most ductile?
a. vanadium
b. mercury
c. germanium
d. astatine
e. xenon
Answer:
mercury
Explanation:
Write
the following separation techniques?
a. Filtration
b. Evaporation
C. Fractional distillation
d. Chromatography
Answer:
Explanation: Fractional distillation
if you aint stephanie dont anwer
Answer:
wsp
Explanation:
Please help, it’s much appreciated
If the hydrogen ion concentration,
[H+], in a solution is 2.65 x 10-2 M,
what is [OH-]?
Answer: acidic
Explanation:
Answer:
3.77 x 10^-13 M
Explanation:
HELP ASAP DUE IN 5 MINUTES WILL GIVE BRAINLIEST
Energy is conserved within a system, meaning that forms of energy are either transferred or transformed as they interact with objects. Which of the statements below correctly describe how energy is transferred or transformed in daily life?
Group of answer choices
Kinetic energy transforms into thermal energy when a heating pad is turned on.
Electrical energy is transferred into light energy so that a flashlight generates light when it’s turned on.
Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street.
Nuclear energy is transferred to electrical energy to provide electricity for our homes.
Answer:
i do believe it is C. Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street. but if i am wrong plz don't come at me but i believe that is right
Explanation:
Answer:
i do believe it is C. Chemical energy in food is transformed into mechanical energy as our body rides a bicycle down the street. but if i am wrong plz don't come at me but i believe that is right
Explanation:
a sample of helium gas is in a sealed rigid container
is there a question or no? im confused.
What temperature units
should be used when
performing calculations using
Charles's Law?
Answer:
Kelvin (K) onlyExplanation:
Kelvin is preferred for solving problems related to Charles' Law because , it is the Absolute temperature scale.
To convert Celsius to Kelvin scale, you add 273 to the temperature in the centigrade/Celsius scale.
What would have a higher boiling point water or hydrocarbon ( from penny liquid stacking)
Answer:
Im pretty sure its hydrocarbon
Explanation:
What will happen to the following equilibrium if Cl2
was removed ?
4HCI(9) + O2(9) = 2012(9) + 2H20(9)
The following equilibrium will shift in the direction of the product:
Further explanationGiven
Reaction
4HCl + O₂ → 2H₂O + 2Cl₂
Cl₂ was removed
Required
Equilibrium changes
Solution
Reaction = - action
adding the products ⇒ Shifts in the direction of the reactants
reducing the products ⇒Shifts in the direction of the products
Cl₂ as a product, so if Cl₂ is taken or reduced, the reaction will try to maintain system equilibrium by moving to the right (product formation) ⇒ Shift in the direction of the product:
Which is larger: barium atom or a barium ion? Explain your answer in terms of atomic structure
A different brand of iron tablet was analysed by Hitration with 0.0093 mol.L" potassium
dichromate via the reaction listed below;
Cr2O72- + 6Fe2+ + 14H+ + 2Cr3+ + 6Fe3+ + 7H20
In this experiment 4 tablets were crushed and dissolved in 200 cm3 of dilute acid. 25cm3
of this solution was used in the titration. The results of the titrations were as follows;
Titration Volume dichromate (cm)
1
33.0
2
32.05
3
32.15
4
32.10
Calculate the concentration of iron used in the titration (4 dp).
C1V1/C2V2 = n/n2
The concentration of iron used in the titration : 0.009 M
Further explanationGiven
Reaction
Cr₂O₇²⁻ + 6Fe²⁺ + 14H⁺ ⇒ 2Cr³⁺ + 6Fe³⁺ + 7H₂O
0.0093 mol/L potassium dichromate
200 cm³ of dilute acid, 25cm³ was used in the titration.
Required
the concentration of iron
Solution
Titration formula
C₁V₁n₁=C₂V₂n₂⇒ From equation : n₁=6n₂(1=Cr₂O₇, 2=Fe)
titration average : 33+32.05+32.15+32.1 / 4 = 32.325 cm³(ml)
25 cm³ of iron solution used in titration :
[tex]\tt V_1=32.325~ml\\\\V_2=25~ml\\\\C_1=0.0093~M\\\\\\\\C_1.V_1.n_2=C_2.V_2.n_1\\\\0.0093\times 32.325\times 6=C_2\times 25\times 1\\\\C_2=0.07215~M[/tex]
Dilution(25 ml from 200 ml iron solution)
[tex]\tt C_2.V_2=C_1.V_1\\\\0.007215\times 25=C_1\times 200\\\\C_1=0.009~M[/tex]
At room temperature (20 °C), milk turns sour in about 64 hours. In a refrigerator at 3 °C, milk can be stored three times as long before it sours.
(a) Estimate the activation energy of the reaction that causes the souring of milk.
(b) How long should it take milk to sour at 40 °C?
Answer: Since k2 corresponds to 64 hours, the time for the milk to sour at 40 C is 64 h / 9.38 = 6.8 hours.
Explanation:
At temperature T1, the Arrhenius Equation is:
k1 = Ae^(-Ea/RT1).
An equivalent equation can be written at T2:
k2 = Ae^(-Ea/RT2).
If these equations are divided, then A cancels:
k1/k2 = e^(-Ea/RT1)/e^(-Ea/RT2)
Taking the natural log:
ln(k1/k2) = (Ea/RT2)-(Ea/RT1);
or:
ln(k1/k2) = (Ea/R)(1/T2 - 1/T1)
We can infer from the question that the milk sours 3 times as fast at the higher temperature (let's call it T1), so we can arbitrarily call k2 = 1 and k1 = 3.
a) Substitute:
ln(3) = (Ea/R)(1/276.15 K - 1/293.15 K).
We get Ea/R = 5231.6. Multiply this by whatever value of R you choose to get Ea in your favorite energy unit. Remember the sig figs.
b) Again, let's let the lower temperature = T2, since we have defined k2 = 1:
ln(k1) = (5231.6)(1/276.15 K - 1/313.15);
ln(k1) = 2.24, so k1 = 9.38.
Since k2 corresponds to 64 hours, the time for the milk to sour at 40 C is 64 h / 9.38 = 6.8 hours.
Please help with this....thank you
Answer:
large cracks suddenly form
Explanation:
the tectonic plates begin to move causing cracks. I think
Which is the noble gas configuration for 31 Ga?
Answer:
1s22s22p63s23p63d104s24p1.
Explanation:
Gallium, Ga has 31 protons and 31 electrons.
Answer:
Ar 3d10 4s2 4p1
Explanation:
hope this serves you well!!
Balance this equation.
_Mg +_Cl2 -->_MgCl2
Answer:
1Mg + 1Cl2 = 1MgCl2
Explanation:
Hi! When balancing an equation, you want to make sure that there are equal amounts of each element on both sides. When looking at the equation that you provided in the question, look and count how many of each element are on each side. I can see that there is 1 Mg ion on the left and 1 Mg ion on the right. There are also 2 Cl ions on the left and 2 Cl ions on the right. Because they are already equal, the coefficients in front of each compound will be 1. If the amounts were different on each side, that is when you would need to add different coefficients.
Hope this helps! Let me know if you have any other questions about this!
Solve for x in the following equation?
v=w/x
Answer:
x = w/v
General Formulas and Concepts:
Pre-Algebra
Equality PropertiesExplanation:
Step 1: Define
v = w/x
Step 2: Solve for x
Multiply x on both sides: xv = wDivide v on both sides: x = w/v