I need help with number 19 A through D

The ΔH° for the given reaction including the given compounds is 19kJ.

To calculate ΔH° for the given reaction, the standard enthalpies of formation (ΔH°f) for each of the compounds involved are used. The equation to calculate ΔH° is considering the standard enthalpies:

ΔH° = ΣΔH°f(products) - ΣΔH°f(reactants)

Using the given values for ΔH°f, we get:

ΔH° = [3(-272 kJ/mol) + (-393.5 kJ/mol)] - [(-1118 kJ/mol) + (-110.5 kJ/mol)]

ΔH° = [-816 kJ/mol - 393.5 kJ/mol] - [-1228.5 kJ/mol]

ΔH° = -1209.5 kJ/mol + 1228.5 kJ/mol

ΔH° = 19 kJ/mol

Therefore, the answer is (c) 19 kJ.

To learn more about enthalpies, click here:
https://brainly.com/question/16720480

#SPJ11

In the aforementioned reaction, the CH₃OH proton is taken up by the OH group. One water molecule is thus eliminated as a result by using stereochemistry.

A secondary carbocation is produced after the elimination, which then undergoes a 1, 2-hydrogen LiAl shift to produce a more stable tertiary carbocation. Moreover, the tertiary carbocation H₂O receives electrons from the alkene, forming a cyclic molecule.

The area of chemistry known as stereochemistry is concerned with analysing the many spatial configurations of atoms in molecules. A brief history lesson is usually necessary before learning about stereochemistry, CH₃OH which is a methodical explanation of a specific area of science and technology. The enantiomers of chiral substances are referred to using the right-hand and left-hand nomenclature AlCl⁻ .

The investigation of a molecule's three-dimensional structure is known as stereochemistry. The only structural difference between the trans and cis isomers of a molecule is where the atoms are located in three-dimensional space. LiOH₂ These stereoisomers have various chemical and physical characteristics.

The mechanism is demonstrated below:

Learn more about stereochemistry here

https://brainly.com/question/29871297

#SPJ1

The statement "molecules move in random directions when heated in a heat engine, and because of the lack of uniformity in the direction of molecular movement" is true.

When a heat engine is heated, molecules absorb heat energy and their kinetic energy increases. The kinetic energy of molecules causes them to move around. However, this movement is not uniform, and the molecules move in random directions.

A heat engine is a device that converts thermal energy into mechanical energy. Heat engines operate on the principle of thermodynamics.

They work by taking in thermal energy from a high-temperature reservoir, converting some of it into mechanical energy, and then releasing the remaining thermal energy to a low-temperature reservoir.The internal combustion engine in a car, the steam engine in an old locomotive, and the turbine in a power plant are all examples of heat engines. They all convert heat energy into mechanical energy to perform work.

To learn more about engine visit;

https://brainly.com/question/31140236

#SPJ11

Answer:

A. light energy is used in photosynthesis and created by respiration

Explanation:    The relocation of organisms across geographical boundaries occurs naturally by various means. Since humans began exploring the globe, however, the rate of new species being introduced into regions has greatly increased. In some cases, humans have dispersed species on purpose; for instance, many plants were transported from Europe to North America for agricultural and ornamental purposes. Others were transported accidentally by ship, train, airplane - even on the shoes of hikers.

     Some species may be introduced and not be able to survive in their new habitat. Others may find optimal conditions for growing, reproducing, and adapting to the new environment, and their populations soar. For instance, lack of predators may contribute to their rapid population increases.

Manipulation of the independent variable directly, Extraneous variable control, Extraneous variable control, statistically correct for the variable's influence.

define experimental ?

relating to, based on, or having the nature of experiment: an experimental study. based on or derived from experience; empirical: experimental evidence. tending to experiment: an experimental artist. tentative or provisional: an experimental rule in football.

an experimental science. relating to, developed from, or founded on experiment: an experimental science. of the nature of an experiment; provisional:

The new software is still in the testing phase.

An experimental aeroplane is one that is in the process of being tested.

based on or drawn from experience; empirical: experimental knowledge.

To learn more about experimental follow the given link: https://brainly.com/question/28240865

#SPJ4

Answer:

they all have the same amount of kinetic energy

Q1. The formula for the energy levels of hydrogen is E = -13.6 eV/n².

Q2. a) The wavelength for the transition between n=1 and n=6 is approximately 93.5 nm. b) The wavelength for the transition between n=25 and n=26 is approximately 29.46 nm.

Q3. For the transitions in Q2, the relative densities are approximately 0.73 and 0.995, respectively.

Q4. The Lambert-Beers law relates the intensity of light transmitted through an absorber to the absorber's density, cross section for absorption, and position within the medium. It is expressed as I(x) = I₀ * exp(-n * σ(λ) * x).

Q1. The formula for the energy levels of hydrogen is given by the Rydberg formula, which is used to calculate the energy of an electron in the hydrogen atom:

E = -13.6 eV/n²

Where:

- E is the energy of the electron in electron volts (eV).

- n is the principal quantum number, which represents the energy level or shell of the electron.

Q2. a) To find the wavelength (in nm) for a transition between n=1 and n=6 in hydrogen, we can use the Balmer series formula:

1/λ = R_H * (1/n₁² - 1/n₂²)

Where:

- λ is the wavelength of the photon emitted or absorbed in meters (m).

- R_H is the Rydberg constant for hydrogen, approximately 1.097 x 10⁷ m⁻¹.

- n₁ and n₂ are the initial and final energy levels, respectively.

Plugging in the values, we have:

1/λ = (1.097 x 10⁷ m⁻¹) * (1/1² - 1/6²)

1/λ = (1.097 x 10⁷ m⁻¹) * (1 - 1/36)

1/λ = (1.097 x 10⁷ m⁻¹) * (35/36)

1/λ = 1.069 x 10⁷ m⁻¹

λ = 9.35 x 10⁻⁸ m = 93.5 nm

Therefore, the wavelength for the transition between n=1 and n=6 in hydrogen is approximately 93.5 nm.

b) Similarly, to find the wavelength (in nm) for a transition between n=25 and n=26 in hydrogen, we can use the same formula:

1/λ = R_H * (1/n₁² - 1/n₂²)

Plugging in the values:

1/λ = (1.097 x 10⁷ m⁻¹) * (1/25² - 1/26²)

1/λ = (1.097 x 10⁷ m⁻¹) * (1/625 - 1/676)

1/λ = (1.097 x 10⁷ m⁻¹) * (51/164000)

1/λ = 3.396 x 10⁴ m⁻¹

λ = 2.946 x 10⁻⁵ m = 29.46 nm

Therefore, the wavelength for the transition between n=25 and n=26 in hydrogen is approximately 29.46 nm.

Q3. To determine the relative density for each of the transitions in Q2, we need to calculate the ratio of the photon flux between the two states. The relative density is given by the equation:

Relative Density = (I(x2) / I(x1))

Where I(x2) and I(x1) are the photon fluxes at positions x2 and x1, respectively.

For a gas temperature of 300K, the relative density is proportional to the Boltzmann distribution of states, which is given by:

Relative Density = exp(-ΔE/kT)

Where ΔE is the energy difference between the two states, k is the Boltzmann constant (approximately 1.38 x 10⁻²³ J/K), and T is the temperature in Kelvin.

a) For the transition between n=1 and n=6, the energy difference is:

ΔE = E₁ - E₂ = (-13.6 eV / 1²) - (-13.6 eV / 6²)

ΔE = -13.6 eV + 0.6 eV = -13.0 eV

Converting the energy difference to joules:

ΔE = -13.0 eV * 1.6 x 10⁻¹⁹ J/eV = -2.08 x 10⁻¹⁸ J

Substituting the values into the relative density equation:

Relative Density = exp(-(-2.08 x 10⁻¹⁸ J) / (1.38 x 10⁻²³ J/K * 300 K))

Relative Density ≈ 0.73

Therefore, for the transition between n=1 and n=6, the relative density is approximately 0.73.

b) For the transition between n=25 and n=26, the energy difference is:

ΔE = E₁ - E₂ = (-13.6 eV / 25²) - (-13.6 eV / 26²)

ΔE ≈ -13.6 eV + 0.0585 eV ≈ -13.5415 eV

Converting the energy difference to joules:

ΔE ≈ -13.5415 eV * 1.6 x 10⁻¹⁹ J/eV ≈ -2.1664 x 10⁻¹⁸ J

Substituting the values into the relative density equation:

Relative Density = exp(-(-2.1664 x 10⁻¹⁸ J) / (1.38 x 10⁻²³ J/K * 300 K))

Relative Density ≈ 0.995

Therefore, for the transition between n=25 and n=26, the relative density is approximately 0.995.

Q4. Derivation of the Lambert-Beers law:

To derive the Lambert-Beers law, we consider a thin slice of the absorber with thickness dx. The intensity of light passing through this slice decreases due to absorption.

The change in intensity, dI, within the slice can be expressed as the product of the intensity at that position, I(x), and the fraction of light absorbed within the slice, nσ(λ)dx:

dI = -I(x) * nσ(λ)dx

The negative sign indicates the decrease in intensity due to absorption.

Integrating this equation from x = 0 to x = x (the total thickness of the absorber), we have:

∫[0,x] dI = -∫[0,x] I(x) * nσ(λ)dx

The left-hand side represents the total change in intensity, which is equal to I₀ - I(x) since the initial intensity is I₀.

∫[0,x] dI = I₀ - I(x)

Substituting this into the equation:

I₀ - I(x) = -∫[0,x] I(x) * nσ(λ)dx

Rearranging the equation:

I(x) = I₀ * exp(-nσ(λ)x)

This is the Lambert-Beers law, which shows the exponential decrease in intensity (photon flux) as light passes through an absorber. The law quantifies the dependence of intensity on the density of the absorber, the absorption cross section, and the position within the absorber.

To know more about Lambert-Beers law, refer to the link below:

https://brainly.com/question/30404288#

#SPJ11

In picture one, there are four electrons, one valance electrons and two shells, in image two there are three electrons, one valance electrons and two shells whereas there are 13 electrons, three valance electrons and three shells.

Electrons:

An electron is a negatively charged particle which can be either bounded with to an atom. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure.

Valence Electrons:

Valence electrons are those electrons which are present in outermost shell or in valence shell or energy level of an atom. For example, oxygen has six valence electrons, two in the 2s subshell and four in the 2p subshell.

Electron Shells Numbers:

Each shell can contain only a fixed number of electrons: the first shell can hold up to two electrons, the second shell can hold up to eight (2 + 6) electrons, the third shell can hold up to 18 (2 + 6 + 10) and so on.

So we can conclude that In picture one, there are four electrons, one valance electrons and two shells, in image two there are three electrons, one valance electrons and two shells whereas there are 13 electrons, three valance electrons and three shells.

Learn more about Valence Electrons here: https://brainly.com/question/371590

#SPJ1

To determine the ratio of moles between C3H8 (propane) and C4H10 (butane) in the original mixture, we need to use the stoichiometry of the combustion reaction and the given amounts of CO2 and H2O produced.

First, let's calculate the moles of CO2 and H2O produced:

Molar mass of CO2 = 12.01 g/mol (C) + 2 * 16.00 g/mol (O) = 44.01 g/mol

Moles of CO2 = 3.74 g / 44.01 g/mol ≈ 0.085 mol

Molar mass of H2O = 2 * 1.01 g/mol (H) + 16.00 g/mol (O) = 18.02 g/mol

Moles of H2O = 1.98 g / 18.02 g/mol ≈ 0.11 mol

Next, we can set up the balanced equation for the combustion of propane (C3H8) and butane (C4H10):

C3H8 + 5O2 → 3CO2 + 4H2O (propane)

C4H10 + 6.5O2 → 4CO2 + 5H2O (butane)

From the balanced equations, we can see that for every 3 moles of CO2 produced, there are 1 mole of C3H8 and for every 4 moles of CO2 produced, there are 1 mole of C4H10.

Now, we can calculate the moles of C3H8 and C4H10 based on the moles of CO2 produced:

Moles of C3H8 = 0.085 mol * (1 mol C3H8 / 3 mol CO2) ≈ 0.0283 mol

Moles of C4H10 = 0.085 mol * (1 mol C4H10 / 4 mol CO2) ≈ 0.0213 mol

Therefore, the ratio of moles between C3H8 and C4H10 in the original mixture is approximately 0.0283 mol : 0.0213 mol, which simplifies to 1.33 : 1 (or approximately 4 : 3).

To know more about stoichiometry, visit:

https://brainly.com/question/24384921

#SPJ11

Answer:

by burning the mixture in an electrical furnace to a temp. 640 degree C. to melt both Zinc & Aluminum leaving copper oxide as a powder.

Explanation:

To Find :

The STP moles of 67.2 L CO.

Solution :

We know, molar volume at STP is used to converted into moles by :

1 moles = 22.4 L STP

So, number of moles in 67.2 L CO is :

\(n=\dfrac{67.2}{22.4}\\\\n = 3 \ moles\)

Therefore, number of STP moles are 3.

Hence, this is the required solution.

Answer:

Things that are negatively charged and things that are positively charged pull on (attract) each other. This makes electrons and protons stick together to form atoms. Things that have the same charge push each other away (they repel each other). This is called the Law of Charges.

Explanation:

According to Coulomb, the electric force for charges at rest has the following properties: Like charges repel each other; unlike charges attract. Thus, two negative charges repel one another, while a positive charge attracts a negative charge.

Answer:

Like charges repel each other; unlike charges attract.

Explanation:

Answer:

Hello There!!

Explanation:

I believe the answer is O They form compounds with very bright colors.

hope this helps,have a great day!!

~Pinky~

The statement about noble gases that is correct is D. They form compounds with very bright colors.

Noble gases simply refers to the elements that have similar properties. Noble gases are colorless, odorless, and have very low reactivity.

Examples of noble gases are helium, argon, Krypton, xenon, etc. Noble gases also form compounds with very bright colors.

In conclusion, the correct option is D.

Read related link on:

https://brainly.com/question/24070118

The mass percent of the solution is approximately 10.51%.

To calculate the mass percent of the solution, we need to determine the total mass of the solution.

The mass of the solution can be calculated using the density and volume of the solution:

Mass of the solution = Density × Volume

Mass of the solution = 1.06 g/ml × 895 ml

Mass of the solution = 948.7 g

The mass percent of the solution can be calculated by dividing the mass of the solute (CSI) by the mass of the solution and multiplying by 100:

Mass percent = (Mass of CSI / Mass of the solution) × 100

Mass percent = (99.7 g / 948.7 g) × 100

Mass percent ≈ 10.51%

Learn more about mass  here

https://brainly.com/question/11954533

#SPJ11

Answer:

In the followings below, the one that doesn't attract to magnets is:

Option 4, Aluminum.

Explanation:

Mainly because of the aluminum's crystal structure.

Hope this helped you out! ^^

#CarryOnLearning

Answer:

Aluminum

Explanation:

Ferromagnetic Metals

Ferromagnetic metals and alloys are the only magnetic metals. Out of all of the elements on the periodic table, there are only 3 metals that are attracted to magnets: iron, nickel, cobalt.

Aluminum

Aluminum is a nonferrous metal (meaning not including iron or steel) that does not include any ferromagnetic metals. Additionally, aluminum itself is not magnetic, so there is no attraction between aluminum and a magnet.

Answer:

b

Explanation:

Answer:

D. the quantity of heat that is required to raise 1 g of the sample by 1°C (or Kelvin) at a given pressure

Explanation:

Answer:

An atom is made of protons and neutrons which make up the nucleus and electrons that are around the nucleus. Although almost all the mass of an atom is in the nucleus, most of the space that the atom takes up is occupied by the electrons.

In very simple terms, the electrons are in orbits around the nucleus so most of the volume of the atom is empty space within the volume that the electrons occupy. The behaviour of the electrons is often assumed to be orbits but their actual positions are not that simple.

As a final note, all atoms contain neutrons with the exception of hydrogen which can exist as one proton and one electron.

Explanation:

Answer:

71%

Explanation:

The thermometer will read -10°C after about 2.43 minutes.

(a) After four more minutes, the thermometer will read -1°C.

This is because the temperature difference between the room and outdoors is (24 - (-11)) = 35°C.

The thermometer then rises 7°C in one minute, so the thermometer is heated at 7°C/minute, i.e. 35°C in five minutes.

So the temperature of the thermometer after 4 more minutes is 7°C + 7°C + 7°C + 7°C = 28°C, 28°C - 35°C = -7°C, -7°C - 3°C = -10°C.

Thus the reading on the thermometer will be -1°C after four more minutes.

(b) To find out when the thermometer will read -10°C, use the formula:

time = (temperature difference ÷ heating rate) + time to start

       = (-10°C - 7°C) ÷ 7°C/minute + 1 minute

       = -17°C ÷ 7°C/minute + 1 minute≈ -2.43 minutes

Thus, the thermometer will read -10°C after about 2.43 minutes.

Learn more about thermometer from the given link

https://brainly.com/question/2339046

#SPJ11  

A sample of nickel containing 3.10 mol contains 182 g of nickel (to three significant figures)

Nickel is a chemical element with the symbol Ni and atomic number 28. It is a silvery-white metal with a slight golden tinge that is ductile and malleable. Nickel is a transition metal and is known for its high resistance to corrosion, as well as its ability to retain its strength and ductility at high temperatures. These properties make nickel a valuable material in many industrial and commercial applications, including the production of stainless steel, batteries, and electronic components. The molar mass of nickel (Ni) is 58.69 g/mol. To calculate the mass of 3.10 mol of nickel, we can use the following formula: mass = number of moles x molar mass

mass = 3.10 mol x 58.69 g/mol

mass = 182 g (to three significant figures )

To learn more about molar masshere:

https://brainly.com/question/22997914

#SPJ1

Answer:

A

Explanation:

Answer:

To calculate the binding energy per mole of 135I, we need to first determine its mass defect (Δm) using the atomic masses of its constituents:

Mass of 135I atom = 134.910023 amu

Mass of 53 protons = 53 x 1.007825 amu = 53.421325 amu

Mass of 82 neutrons = 82 x 1.008665 amu = 82.82893 amu

Total mass of 135I nucleus = 53.421325 amu + 82.82893 amu = 136.250255 amu

Δm = (mass of 135I atom) - (total mass of 135I nucleus)

= 134.910023 amu - 136.250255 amu

= -1.340232 amu

The binding energy (BE) can be calculated from the mass defect using Einstein's famous equation:

BE = Δm x c^2

where c is the speed of light in a vacuum (299,792,458 m/s).

BE = -1.340232 amu x (1.66054 x 10^-27 kg/amu) x (299,792,458 m/s)^2 / (6.02214 x 10^23 atoms/mol) / 1000 J/kJ

= -2.2008 x 10^-11 J/atom

Multiplying by Avogadro's number (6.02214 x 10^23 atoms/mol) gives the binding energy per mole:

BE/mol = -2.2008 x 10^-11 J/atom x (6.02214 x 10^23 atoms/mol) / 1000 J/kJ

= -1.3241 x 10^4 kJ/mol

Rounding to 3 significant figures and expressing in exponential format gives the final answer of -1.32e4 kJ/mol.

Explanation:

please follow me for more if you need any help

Answer:

Option B. K = 1.3×10⁴, product favored

Explanation:

Data obtained from the question include:

O2(g) + 2SO2(g) <==> 2SO3(g)

Concentration of O2, [O2] = 0.024 M

Concentration of SO2, [SO2] = 0.015 M

Concentration of SO3, [SO3] = 0.26 M

Equilibrium constant, K =..?

The equilibrium constant, K is simply defined as the ratio of the concentration of products raised to their coefficient to the concentration of the reactants raised to their coefficient.

The equilibrium constant for the above reaction can be written as

K = [SO3]² / [O2] [SO2]²

Inputing the values of [SO3], [O2] and [SO2] the equilibrium constant, K is:

K = [SO3]² / [O2] [SO2]²

K = 0.26² / 0.024 × 0.015²

K = 1.3×10⁴

Therefore, the equilibrium constant K is 1.3×10⁴.

Since the value of the equilibrium constant, K is large and positive, therefore, the reaction favours the product.

Claim: The separation of Mesosaurus fossils can be explained by the continental drift hypothesis. Evidence: Fossil Distribution, Geological Similarities, Matching Climate and Habitat. The distribution of Mesosaurus fossils across South America and Africa, the geological similarities between these regions, and the matching climate and habitat conditions all support the claim that the separation of Mesosaurus populations can be explained by the process of continental drift.

Claim: The separation of Mesosaurus fossils can be explained by the continental drift hypothesis.

Evidence:

Fossil Distribution: Mesosaurus fossils are found in both South America and Africa. This distribution aligns with the hypothesis of continental drift, which suggests that these continents were once connected and later separated. The similarity in fossil remains on different continents supports the claim that Mesosaurus populations were separated when the continents drifted apart.

Geological Similarities: The geological formations and sedimentary layers in which Mesosaurus fossils are found in South America and Africa display remarkable similarities. This similarity implies that these regions were once part of the same landmass and were subsequently separated. The matching geological features provide further evidence for the separation of Mesosaurus populations due to continental drift.

Matching Climate and Habitat: Mesosaurus fossils indicate that the species was adapted to a freshwater environment. The presence of similar freshwater environments in both South America and Africa further supports the claim that Mesosaurus populations were separated when the continents drifted apart. The matching climate and habitat conditions provide evidence that supports the idea of geographic isolation and subsequent speciation.

In conclusion, the distribution of Mesosaurus fossils across South America and Africa, the geological similarities between these regions, and the matching climate and habitat conditions all support the claim that the separation of Mesosaurus populations can be explained by the process of continental drift.

For more question on climate

https://brainly.com/question/29617595

#SPJ8

Answer:

5.55 L

Explanation:

This excersise can be solved by the Boyle's law.

This law for gases states that the pressure of a gas in a vessel is inversely proportional to the volume of the vessel.

P₁ . V₁  = P₂ . V₂

The law comes from the Ideal Gases Law, in the first term.

P . V = n . R . T  In this case, n . R . T are all constant.

6.35 L . 88.6 kPa = 101.3 kPa . V₂

V₂ = (6.35 L . 88.6 kPa) / 101.3 kPa

V₂ = 5.55 L

It is inversely proportional because, as it happened in this case, pressure was increased, therefore volume decreased.

Answer:

atomic number

Explanation: