Answer:
ΔH of the reaction is -802.3kJ.
Explanation:
Using Hess's law, you can know ΔH of reaction by the sum of ΔH's of half-reactions.
Using the reactions:
(1) Cgraphite(s)+ 2H₂(g) → CH₄(g) ΔH₁ = −74.80kJ
(2) Cgraphite(s)+ O₂(g) → CO₂(g) ΔH₂ = −393.5k J
(3) H₂(g) + 1/2 O₂(g) → H₂O(g) ΔH₃ = −241.80kJ
The sum of (2) - (1) produce:
CH₄(g) + O₂(g) → CO₂(g) + 2H₂(g) ΔH' = -393.5kJ - (-74.80kJ) = -318.7kJ
And the sum of this reaction with 2×(3) produce:
CH₄(g) + 2 O₂(g) → CO₂(g) + 2H₂O(g) And ΔH = -318.7kJ + 2×(-241.80kJ) =
-802.3kJ
Which process is used to make lime (calcium oxide) from limestone (calcium carbonate)?
Answer:
Explanation:
Calcium oxide is fromed by the decomopostion of CaCO3 at high temperature.
CaCO3 ------> CaO +CO2
Hope this helps you
How is excitation in spectroscopy brought about
Answer: the exciation of molecules is brount by absorption of energy in spectroscpy
Explanation:
A student takes a measured volume of 3.00 M HCl to prepare a 50.0 mL sample of 1.80 M HCI. What volume of 3.00 M HCI
did the student use to make the sample?
Use M,V;-MV
3.70 mL
16.7 ml
30.0 mL
83.3 mL
Mark this and return
Save and Exit
Next
Submit
Answer:
30 mL VOLUME OF 3.0 M HCl SHOULD BE USED BY THE STUDENT TO MAKE A 1.80 M IN 50 mL OF HCl.
Explanation:
M1 = 3.00 M
M2 = 1.80 M
V2 = 50 .0 mL = 50 /1000 L = 0.05 L
V1 = unknown
In solving this question, we know that number of moles of a solution is equal to the molar concentration multiplied by the volume. To compare two samples, we equate both number of moles and substitute for the required component.
So we use the equation:
M1 V1 = M2 V2
V1 = M2 V2 / M1
V2 = 1.80 * 0.05 / 3.0
V2 = 0.09 /3.0
V2 = 0.03 L or 30 mL
To prepare the sample of 1.80 M HCl in 50.0 mL from a 3.0 M HCl, 30 mL volume should be used.
Answer:
C on edg 2021Explanation:
i dont like reading
how many grams of H2 are needed to produce 14.34 g of NH3?
please help, this hw is due in a few hours
Answer:
im pretty sure its 2.54g H2
Explanation:
14.34gNH3 / 17.03gNH3 <-- molar mass
.842g x 3 mol <-- mols of H2
2.52 / 2 mol <-- mols of NH3
1.26 x 2.016gH2= 2.54gH2
What are plastic bottles made of?
Polyethylene
halogen
silicon
Alkyl groups
Answer:
polyethylenes
Explanation:
the plastic bottles used to hold potable water and other drinks are made from polyethylene because, the material is both strong and light.
hope this helped!
Answer: Polyethylenes
Explanation: I got 100% on the test :)
Which process is a physical change
Answer:
a physical change is something that has not been modified chemically and can possibly be changed back to the state it was once before. A physical change keeps all the same atoms and none of them is modified.
Example:
When a block of clay is morphed into a giraffe statue, it can be morphed back to its original state. If someone burnt the block of clay, the atoms would be modified and it would be unable to go back to its previous state.
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(If you're referring to a question with these answers)
A. iron rusting
B. milk turning to curd
C. water boiling
D. paper burning
E. hard water staining pipes
-----------------------------------------------------------------------------------------------------------------
Answer:
C. Water Boiling
(If you are referring to a question with these answers I think this is the correct answer if not I do apologize)
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The temperature program for a separation starts at a temperature of 50 °C and ramps the temperature up to 270 °C at a rate of 10 °C/minute. Which statement is NOT true for this separation?
A) At 10 °C/minute, a total of 22 minutes is needed to reach 270 oC.
B) Strongly retained solutes will remain at the head of the column while the temperature is low.
C) Weakly retained solutes will separate and elute early in the separation.
D) The vapor pressure of strongly retained solutes will increase as temperature increases.
E) Strongly retained analytes will give broad peaks.
Answer:
The correct answer to the question is Option E (Strongly retained analytes will give broad peaks).
Explanation:
The other options are true because:
A. Initial temp = 50 °C
Final temp = 270 °C
Differences in temp = 270 - 50 = 220°C
Rate = 10 °C/minute.
So, at 10 °C/minute,
total of 220°C /10 °C = number of minutes required to reach the final temp.
220/10 = 22 minutes
B. A column has a minimum and maximum use temperature. Solutes that are already retained would remain stationary while temperatures are low. This would only change if there is an increase in temperature. Heat transfers more energy to the liquid which would make the solute interact with the column phase.
C. Weakly retained solutes may contain larger molecules, will separate by absorbing into the solvent early in separation making the mobile phase separates out into its components on the stationary phase.
D. Retained solute's vapor pressure is higher at higher temperatures making it possible for particle to escape more from the solute when the temperature is high than when it is low.
The height of the sun in the sky at noontime is called
Answer:
It is called 'solar noon'
Explanation:
It's when the sun is at its highest
And also the moment the sun crosses the meridian.
Classify the following as Arrhenius, Bronsted-Lowry, or Lewis acid-base reactions. A reaction may fit all, two, one, or none of the categories:I. Cu2+ + 4 Cl− CuCl42−II. Al(OH)3 + 3HNO3 Al3+ + 3H2O + 3 NO3−III. N2 + 3 H2 2NH3IV. CN− + H2O HCN + OH
Answer:
I. Lewis acid-base reaction
II. Arrhenius, Brønsted-Lowry, and Lewis' acid-base reaction
III. Brønsted-Lowry and Lewis'acid-base reaction
IV. Lewis acid-base reaction
Explanation:
According to Arrhenius, an acid is a substance that dissolves in water to produce H+ ions, and a base is a substance that dissolves in water to produce hydroxide (OH−) ions.
In the reaction below, AH is an avid, BOH is a base reacting together to form a salt(A-B+) and water only.
AH + BOH ---> A-B+ + H2O
According to Brønsted-Lowry definition, an acid is any substance that can donate a proton, and a base is any substance that can accept a proton.
In the reaction below, AH is an acid while B is a base, reacting together to form an acid-base conjugate pair.
AH + B <-----> BH+ + A-
According to Lewis' definition, an acid is a species that accepts an electron pair while a base donates an electron pair resulting in a coordinate covalently bonded compound, also known as an adduct. In the reaction below, A+ is an acid, B- is a base, reacting together to form product A-B.
A+ + B- ------> A-B
Considering the above definitions;
I. Cu²+ + 4 Cl− ---> CuCl4²− is a Lewis acid-base reaction because it involves electron sharing only.
II. Al(OH)3 + 3HNO3 ---> Al3+ + 3H2O + 3 NO3− is an Arrhenius, Brønsted-Lowry, and a Lewis acid-base reaction because it involves protons, electrons and hydroxide ions.
III. N2 + 3 H2 ---> 2NH3 is a Lewis acid-base reaction because it involves sharing of electrons only.
IV. CN− + H2O ---> HCN + OH is both a Lewis and Brønsted-Lowry acid-base reaction because both protons and electrons sharing is involved.
In a Bronsted-Lowry acid-base reaction reaction, an acid donates protons which is accepted by the base.
The following are useful definitions of acids and bases;
An Arrhenius acid produces hydrogen ion as its only positive ion in solution while an Arrhenius base produces hydroxide ion as its only negative ion in solution.A Bronsted-Lowry acid donates hydrogen ions while a Bronsted-Lowry base accepts hydrogen ionsA Lewis acid accepts lone pairs of electrons while a Lewis base donates lone pairs of electrons.Based on these, we can now classify the reactions accordingly;
Cu^2+ + 4Cl− ------>[CuCl4[^2− Lewis acid-base reaction Al(OH)3 + 3HNO3 -----> Al^3+ + 3H2O + 3NO3^− Arrhenius acid-base reactionN2 + 3H2 ----> 2NH3 NoneCN− + H2O ------> HCN + OH^- Bronsted-Lowry acid-base reactionLearn more: https://brainly.com/question/9352088
Which statement best describes information that would be associated with science rather than with pseudoscience?
Answer:
The information has been changed to support a claim
Explanation:
The acetate ion is the conjugate base of the weak acid acetic acid. The value of Kb for CH3COO-, is 5.56×10-10. Write the equation for the reaction that goes with this equilibrium constant.
Answer: The equation for the reaction that goes with this equilibrium constant is [tex]5.56\times 10^{-10}=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
Explanation:
[tex]CH_3COOH\rightarrow CH_3COO^-+H^+[/tex]
Here [tex]CH_3COOH[/tex] donates a proton and thus behaves as an acid and forms [tex]CH_3COO^-[/tex] which is called as the conjugate base of [tex]CH_3COOH[/tex]
The dissociation constant of acids is given by the term [tex]K_a[/tex] and the dissociation constant of bases is given by the term [tex]K_b[/tex] and is defined as the ratio of concentration of products to the concentration of reactants each raised to the power their stoichiometric ratios.
[tex]K_a[/tex] for [tex]CH_3COOH[/tex] :
[tex]K_a=\frac{[CH_3COO^-]\times [H^+]}{[CH_3COOH]}[/tex]
[tex]CH_3COO^-+H^+\rightarrow CH_3COOH[/tex]
[tex]K_b=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
[tex]5.56\times 10^{-10}=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
The equation for the reaction that goes with this equilibrium constant is [tex]K_b=\frac{[CH_3COOH]}{[CH_3COO^-]\times [H^+]}[/tex]
carbon dioxide is a non-polar molecule true or false
Answer:
True
Explanation:
Due to the arrangement of the molecule, a carbon dioxide molecule is non-polar.
Problem PageQuestion Liquid hexane CH3CH24CH3 will react with gaseous oxygen O2 to produce gaseous carbon dioxide CO2 and gaseous water H2O. Suppose 60. g of hexane is mixed with 74.5 g of oxygen. Calculate the maximum mass of water that could be produced by the chemical reaction. Round your answer to 3 significant digits.
Answer:
43.45g of water would be produced from the reaction.
Explanation:
Liquid became reacts with oxygen to produce carbon dioxide and water.
This type of reaction is known as combustion reaction between alkanes.
Equation of reaction.
Assuming the reaction occurs in an unlimited supply of oxygen,
2C₆H₁₄ + 19O₂ → 12CO₂ + 14H₂O
From the above equation of reaction,
2 moles of C₆H₁₄ reacts with 19 moles of O₂ to produce 14 moles of H₂O.
To find the theoretical mass,
Number of moles = mass / molar mass
Molar mass of C₆H₁₄ = 86g/mol
Molar mass of O₂ = 16g/mol × 2 = 32g/mol
Molar mass of H₂O = 18g/mol
Mass of H₂O = number of moles × molar mass
Mass of H₂O = 14 × 18 = 252g
Mass of C₆H₁₄ = number of moles × molar mass
Mass of C₆H₁₄ = 2 × 86 = 172g
Mass of O₂ = number of moles × molar mass
Mass of O₂ = 19 × 32 = 608g
From the equation of reaction,
172g of C₆H₁₄ reacts with 608g of O₂ to produce 252g of H₂O
(172 + 608)g of reactants produce 252g of H₂O
780g of reactants produce 252g of H₂O
(60 + 75.5)g of reactants will produce a x g of H₂O
780g of reactants = 252g of H₂O
134.5g of reactants = x g of H₂O
X = (134.5 × 252) / 780
X = 43.45g of H₂O
Therefore, 43.45g of H₂O would be produced from 60g of hexane and 74.5g of oxygen
Answer:
[tex]m_{H_2O}=30.9gH_2O[/tex]
Explanation:
Hello,
In this case, the combustion of hexane is given by:
[tex]C_6H_{14}+\frac{19}{2} O_2\rightarrow 6CO_2+7H_2O[/tex]
The next step is to compute the reacting moles of hexane:
[tex]n_{C_6H_{14}}=60gC_6H_{14}*\frac{1molC_6H_{14}}{86gC_6H_{14}} =0.698molC_6H_{14}[/tex]
Then, the moles of hexane consumed by 74.5 g of oxygen using the molar ratio in the chemical reaction (1:19/2):
[tex]n_{C_6H_{14}}=74.5gO_2*\frac{1molO_2}{32gO_2} *\frac{1molC_6H_{14}}{19/2molO_2} =0.245molC_6H_{14}[/tex]
Therefore, as less moles of hexane are consumed by oxygen, it is in excess, so we compute the mass of water produced by the consumed 0.245 moles of hexane:
[tex]m_{H_2O}=0.245molC_6H_{14}*\frac{7molH_2O}{1molC_6H_{14}}*\frac{18gH_2O}{1molH_2O} \\\\m_{H_2O}=30.9gH_2O[/tex]
Best regards.
What is the predicted order of first ionization energies from highest to lowest for lithium (Li), sodium (Na), potassium (K), and rubidium (Rb)?
Rb > K > Na > Li
K > Rb > Na > Li
Li > Na > K > Rb
Rb > K > Li > Na
Answer:
Li>Na>K>Rb
Explanation:
Answer:
c. Li > Na > K > Rb
Explanation:
edge 2021
(:
An unknown compound, B, has the molecular formula C7H12. On catalytic hydrogenation 1 mol of B absorbs 2 mol of hydrogen and yields 2-methylhexane. B has significant IR absorption band at about 3300 and 2200 cm-1. Which compound best represents B?
a. 5-methyl-1,3-hexadiene
b. 5-methyl-1-hexyne
c. 3-methyl-1-hexyne
d. 5-methyl-2-hexyne
e. 2-methyl-1,5-hexadiene
Answer:
B and D
Explanation:
If we use the info given we have a band a 3300 cm-1 and 2200 cm-1 this indicates that we have an alkyne functional group. Additionally, the hydrogenation of the unknown molecule will consume two moles of hydrogens this fits with the 2 pi bonds in the alkyne functional group. So, we can discard "a" and "e". The product of this hydrogenation is 2-methylhexane therefore we can discard c because the methyl group is placed on carbon 3. Structures b and d can work.
See figure 1
I hope it helps!
Calculate the standard entropy of reaction at 298 K for the reaction Hg(liq) + Cl2(g) → HgCl2(s) The standard molar entropies of the species at that temperature are: Sºm (Hg,liq) = 76.02 J / (K mol) ; Sºm (Cl2,g) = 223.07 J / (K mol) ; Sºm (HgCl2,s) = 146.0 J / (K mol)
Answer:
−153.1 J / (K mol)
Explanation:
Calculate the standard entropy of reaction at 298 K for the reaction Hg(liq) + Cl2(g) → HgCl2(s) The standard molar entropies of the species at that temperature are: Sºm (Hg,liq) = 76.02 J / (K mol) ; Sºm (Cl2,g) = 223.07 J / (K mol) ; Sºm (HgCl2,s) = 146.0 J / (K mol)
Hg(liq) + Cl2(g) → HgCl2(s)
Given that;
The standard molar entropies of the species at that temperature are:
Sºm (Hg,liq) = 76.02 J / (K mol) ;
Sºm (Cl2,g) = 223.07 J / (K mol) ;
Sºm (HgCl2,s) = 146.0 J / (K mol)
The standard molar entropies of reaction = Sºm[products] - Sºm [ reactants]
= 146.0 J / (K mol) – [76.02 J / (K mol) +223.07 J / (K mol) ]
= -153.09 J / (K mol)
= or -153.1 J / (K mol)
Hence the answer is −153.1 J / (K mol)
When 8.1 g of an unknown non-electrolyte is dissolved in 50.0 g of carbon tetrachloride, the boiling point increased by 3.67 degrees C. If the Kbp of the solvent is 4.95 K/m, calculate the molar mass of the unknown solute.
Answer:
218.3 g/mol
Explanation:
Boiling point elevation occurs when a solute is added to a solvent increasing the boiling point of the solution with regard to the pure solvent.
The law is:
ΔT = Kb×m×i
Where ΔT is change in temperature (3.67°C), Kb is the boiling point constant of the solvent (4.95°C/m), m is molality of the solution and i is Van't Hoff factor (1 for a non-electrolyte).
3.67°C = 4.95°C/m×m×i
0.7414m = molality of the solution (Moles solute / kg solvent).
As the mass of the solvent is 50.0g = 0.0500kg:
0.7414m = Moles solute / 0.0500kg
0.0371 = moles of solute
As the mass of the solute is 8.1g, molar mass of the solute (Ratio between mass in g and moles) is:
8.1g / 0.0371mol =
218.3 g/molA microwave has a wavelength of 0.028 m. What us this wavelength in scientific notation
Answer:
2.8 times 10^ -2
Explanation:
scientific notation is supposed to be a number between 1 and 10
the decimal point moves 2 to the right in order to get 2.8 which makes the exponent negative
How would I find the quantity of heat absorbed or released when 2.0g of LiOH is dissolved in 100g of H₂0 when the enthalpy of the solution is -23.6KJ/mol?
Answer:
1.97kJ of energy are released.
Explanation:
The dissolution of LiOH in water is:
LiOH(s) → Li⁺(aq) + OH⁻(aq) ΔH = -23.6kJ
That means, when 1 mole of LiOH is dissolved, there are released (Because of the - in the enthalpy) 23.6kJ
2.0 g of LiOH (Molar mass: 23.95g/mol) are:
2.0g LiOH × (1 mol / 23.95g) =0.0835 moles of LiOH.
As 1 mole of LiOH release 23.6kJ, 0.0835moles release:
0.0835moles × (-23.6kJ / 1mole) = 1.97kJ of energy are released
Which of the following is most likely to make scientific knowledge stronger?
A.) Creating new hypotheses
B.) Lack of observational evidence
C.) Few scientists working towards it
D.) Evaluating it with experimentation and argument
Answer:
D) Evaluating it with experimentation and argument.
Explanation:
If you don't have enough observational evidence, then you can't really strengthen your scientific knowledge, because you haven't collected enough information to answer the questions you're asking.
If you only have a few scientists working on a question, it will take longer to find an answer. With more people working on a concept, it can be solved in more time.
It can be good to create new hypotheses, but only if you've already tested your original hypothesis (with experimentation and argument), and it turned out to be wrong. Once you've rejected your first hypothesis, only then should you make a new one.
Answer:
D
Explanation:
Calculate Keq for these reactions and predict if the equilibrium will lie to the right or to the left as written. (You may enter your answer in scientific notation, e.g. 1.0*10^-9. Enter your answer to two significant figures.) Reaction 1: + + pKa = 9 pKa = 38 Keq = Equilibrium position = _______ Reaction 2: + + pKa = 35 pKa = 25 Keq = Equilibrium position = _______
Complete Question
The complete question is shown on the first uploaded image
Answer:
For reaction 1
[tex]K_{eq} = 10^{29}[/tex]
The equilibrium position is to the right
For reaction 2
[tex]K_{eq} = 10^{-6.66}[/tex]The equilibrium position is to the left
Explanation:
Generally [tex]pKa[/tex] is mathematically evaluated as
[tex]pKa = pKa _ \ {left }} - pKa _ \ {right }}[/tex]
And equilibrium position [tex]K_a[/tex] is mathematically evaluated as [tex]K_{eq} = 10^\ {-pK_a}[/tex]
From the question we are told that
For reaction 1
[tex]pKa_\ {left}} \ = 9[/tex]
[tex]pKa_\ {right }} \ = 38[/tex]
So
[tex]pKa = 9-38[/tex]
[tex]pKa =-29[/tex]
So [tex]K_{eq} = 10^{-(-29)}[/tex]
[tex]K_a = 10^{29}[/tex]
This implies that the equilibrium position is to the right
For reaction 2
[tex]pKa_\ {left}} \ = 15.9[/tex]
[tex]pKa_\ {right }} \ = 9.24[/tex]
So
[tex]pKa = 15.9-9.24[/tex]
[tex]pKa = 6.66[/tex]
So [tex]K_{eq} = 10^{-(6.66)}[/tex]
[tex]K_{eq} = 10^{-6.66}[/tex]
This implies that the equilibrium position is to the left
Real images can be projected onto a screen.
A. True
B. False
Answer:
True
Explanation:
A real image can be projected or seen on a screen but a virtual image cannot because a real image is formed when light rays coming from an object actually meet at a point after refraction through a lens while a virtual image is formed when light rays coming from an object only appear to meet at a point when produced ...
Hope this helps you, and Good luck!
What is the reactant(s) in the chemical equation below?
2Al(s) + 2NaOH(aq) + 2H2O()
2NaAlO2(aq) + 3H2(9)
A. 2Al(s) + 2NaOH(aq) + 2H200)
B. 2NaAlo2(aq) + 3H2(g)
C. 2Al(s)
D. 3H2(g)
Answer:
A
Explanation:
They are all found in the reactants side
Enter your answer in the provided box. A sample of an unknown gas effuses in 14.5 min. An equal volume of H2 in the same apparatus under the same conditions effuses in 2.42 min. What is the molar mass of the unknown gas
Answer:
Molar mass = 71.76 g/mol
Explanation:
The relationship between molar mass and rate of effusion is given as;
Vh / Vu = √ (Mu / Mh)
The rate of effusion of a gas is inversely proportional to the square root of the mass of its particles.
Rate = volume / time (Assuming Volume = 1)
Vh = Rate of effusion of Hydrogen = 1 / 2.42
Vu = Rate of effusion of unknown gas = 1 / 14.5
Mh = Molar mass of hydrogen = 2
Mu = Molar mass of unknown gas = x
Substituting into the formular, we have;
(1 / 2.42) / (1 / 14.5) = √ ( x / 2)
5.99 = √ ( x / 2)
35.88 = x / 2
x = 71.76
Calculate the Kc for the following reaction if an initial reaction mixture of 0.500 mole of CO and 1.500 mole of H2 in a 5.00 liter container forms an equilibrium mixture containing 0.198 mole of H2O and corresponding amounts of CO, H2, and CH4.
Answer:
4.41
Explanation:
Step 1: Write the balanced equation
CO(g) + 3 H₂(g) = CH₄(g) + H₂O(g)
Step 2: Calculate the respective concentrations
[tex][CO]_i = \frac{0.500mol}{5.00L} = 0.100M[/tex]
[tex][H_2]_i = \frac{1.500mol}{5.00L} = 0.300M[/tex]
[tex][H_2O]_{eq} = \frac{0.198mol}{5.00L} = 0.0396M[/tex]
Step 3: Make an ICE chart
CO(g) + 3 H₂(g) = CH₄(g) + H₂O(g)
I 0.100 0.300 0 0
C -x -3x +x +x
E 0.100-x 0.300-3x x x
Step 4: Find the value of x
Since the concentration at equilibrium of water is 0.0396 M, x = 0.0396
Step 5: Find the concentrations at equilibrium
[CO] = 0.100-x = 0.100-0.0396 = 0.060 M
[H₂] = 0.300-3x = 0.300-3(0.0396) = 0.181 M
[CH₄] = x = 0.0396 M
[H₂O] = x = 0.0396 M
Step 6: Calculate the equilibrium constant (Kc)
[tex]Kc = \frac{[CH_4] \times [H_2O] }{[CO] \times [H_2]^{3} } = \frac{0.0396 \times 0.0396 }{0.060 \times 0.181^{3} } = 4.41[/tex]
What will be the final temperature when a 25.0 g block of aluminum (initially at 25 °C) absorbs 10.0 kJ of heat? The specific heat of Al is 0.900 J/g·C.
42.1°C is the final temperature when a 25.0 g block of aluminum (initially at 25 °C) absorbs 10.0 kJ of heat.
What is temperature?The physical concept of temperature indicates in numerical form how hot or cold something is. A thermometer is used to determine temperature. Thermometers are calibrated using a variety of temperature scales, which historically defined distinct reference points or thermometric substances.
The most popular scales include the Celsius scale, sometimes known as centigrade, with the unit symbol °C, the scale of degrees Fahrenheit (°F), or the Kelvin scale (K), with the latter being mostly used for scientific purposes. One of the United Nations System of Units' (SI) seven base units is the kelvin.
Q=725 J
m=55.0 g
c=0.900 J/(°C⋅g)
ΔT=final temperature - initial temperature
ΔT=(x−27.5)°C
725 J=55.0 g⋅0.900 J/(°C⋅g)(x−27.5)
X=42.1°C
Therefore, 42.1°C is the final temperature when a 25.0 g block of aluminum (initially at 25 °C) absorbs 10.0 kJ of heat.
To know more about temperature, here:
https://brainly.com/question/23411503
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The decomposition of Ca(OH)2(s) intoCaO(s) and H2O(g) at constant pressure requires the addition of 109 kJ of heat per mole of Ca(OH)2.
A. Write a balanced thermochemical equation for the reaction.
B. Draw an enthalpy diagram for the reaction, showing the activation energy, Ea, and the enthalpy change for the reaction.
Answer:
A. Ca(OH)2 ----> CaO + H2O; ∆H = +109KJ
B. Check attached document below for the enthalpy diagram
Explanation:
A thermochemical equation is a balanced chemical equation in which enthalpy change is variable. It tells about the nature of the reaction.
Enthalpy change is the difference between the heat content of the products and reactants in a thermochemical equation.
∆H is negative for an exothermic reaction (a reaction where heat is given out), while it is positive for an endothermic reaction ( a reaction in which heat is added).
The activation energy, Ea, is the minimum amount of energy reactant particles must possess in order for a reaction to proceed towards product formation.
As per the decomposition of the Ca(OH) 2 and the CaO the constant pressure needs to be added of the 109KJ.
The balance thermochemical equation for the reaction is expressed as Ca(OH)2 ----> Ca O + H2O; ∆H = +109KJThe diagram for the reaction and the activation energy is given above.Learn more about decomposition.
brainly.com/question/14797703.
A chemistry student is given of a clear aqueous solution at . He is told an unknown amount of a certain compound is dissolved in the solution. The student allows the solution to cool to . At that point, the student sees that a precipitate has formed. He pours off the remaining liquid solution, throws away the precipitates, and evaporates the water from the remaining liquid solution under vacuum. More precipitate forms. The student washes, dries and weighs the additional precipitate. It weighs 50,0 g.
Using only the information above, can you calculate the solubility of X in water at 16. C. If you said yes, calculate it.
Answer:
Solubility cannot be calculated.
Explanation:
To calculate the solubility of X it is necessary to know the value of the mass of the solute (X) that can be dissolved in 100 g of water.
[tex]Solubility = \frac{Solute mass}{100 grams of water}[/tex]
Taking into account that we do not know the value of the mass of the solution, therefore the value of the solubility of the compound cannot be determined.
11. Caproic acid, which is responsible for the foul odor of dirty socks, is composed of C, H, and O atoms. Combustion of a 0.225-g sample of this compound produces 0.512 g CO2 and 0.209 g H2O. (a) What is the empirical formula of caproic acid
Answer:
C3H6O
Explanation:
Step 1:
Data obtained from the question include the following:
Mass of the compound = 0.225g
Mass of CO2 = 0.512g
Mass of H2O = 0.209g
Step 2:
Determination of the masses of carbon, hydrogen and oxygen present in the compound.
This is illustrated below:
For Carbon, C:
Molar mass of CO2 = 12 + (2x16) = 44g/mol
Mass of C in CO2 = 12/44 x 0.512 = 0.1396g
For Hydrogen, H:
Molar mass of H2O = (2x1) + 16 = 18g/mol
Mass of H in H2O = 2/18 x 0.209 = 0.0232g
For Oxygen, O:
Mass of O = 0.225 – (0.1396 + 0.0232)
Mass of O = 0.0622g
Step 3:
Determination of the empirical formula for caprioc acid.
This can be obtain as follow:
C = 0.1396g
H = 0.0232g
O = 0.0622g
Divide by their molar mass
C = 0.1396/12 = 0.0116
H = 0.0232/1 = 0.0232
O = 0.0622/16 = 0.0039
Divide by the smallest
C = 0.0116/0.0039 = 3
H = 0.0232/0.0039 = 6
O = 0.0039/0.0039 = 1
Therefore, the empirical formula for caprioc acid is C3H6O
Aspirin is usually packaged with
A. acetic anhydride
B. salicylic acid
C. buffering agents
Answer:
Aspirin is usually packaged with C. buffering agents.
Explanation:
