For every two QH2 that enter the Q cycle, one is regenerated and the other passes its two electrons to two cytochrome c1 centers. The overall equation is
QH2+2 cyt c1(Fe3+)+2H+→Q+2 cyt c1(Fe2+)+4H+
Calculate the free energy change associated with the Q cycle.

Galileo disproved the Ptolemaic theory, sanctioned for centuries by the Church, which held the Earth to be the central and principal object in the universe, about which all celestial objects orbited.

The new evidence led scientists to change their minds about the geocentric model is that the Sun and stars move across the sky in the same direction everyday. They appear to be going around the Earth. However, Galileo observed moons which orbited Jupiter. This suggests that not everything orbits the Earth and that the geocentric model is not correct.

Geocentric model is any theory of the structure of the solar system (or the universe) in which Earth is assumed to be at the centre of it all.

This model is  often named Ptolemaic model after its most famous supporter, the Greco-Roman astronomer Ptolemy.

The geocentric is often referred to as the Medieval view of the universe and it dominated thinking into the early modern age.

Therefore, The new evidence led scientists to change their minds about the geocentric model is that the Sun and stars move across the sky in the same direction everyday. They appear to be going around the Earth. However, Galileo observed moons which orbited Jupiter. This suggests that not everything orbits the Earth and that the geocentric model is not correct.

Learn more about Geocentric Model, here:

https://brainly.com/question/19757858

#SPJ3

Answer:

D.) State the question, form a hypothesis, conduct an experiment

Explanation:

https://www.colorincolorado.org/article/steps-scientific-process

Answer:si and ge

Explanation:

Both silicon (Si) and arsenic (As) have 5 valence electrons. This means that they both have 5 dots around their chemical symbols in their electron dot diagrams. Thus, option B is correct. The images are attached below.

Phosphorus (P) has 5 valence electrons, but it also has a ground state electron configuration of 1s²2s²2p⁶3s²3p³. This means that phosphorus has 3 dots around its chemical symbol in its electron dot diagram, and 2 dots that are not shown.

Sulfur (S) has 6 valence electrons, but it also has a ground state electron configuration of 1s²2s²2p⁶3s²3p⁴. This means that sulfur has 4 dots around its chemical symbol in its electron dot diagram, and 2 dots that are not shown. Thus, option B is correct.

Learn more about valence electrons, here:

https://brainly.com/question/31264554

#SPJ4

The statement that Kinetic-molecular theory assumes that attractive and repulsive forces between gas particles are stronger than those between gas particles and container walls is false.

Kinetic-molecular theory simply explains that gas particles are typically in constant motion and that they also have perfectly elastic collisions.

Kinetic-molecular theory doesn't assume that attractive and repulsive forces between gas particles are stronger than those between gas particles and container walls.

Lastly, in kinetic-molecular theory, the particles exert no force on each other.

In conclusion, the correct option is false.

Read related link on:

https://brainly.com/question/23859331

The question is incomplete; the complete question is;

Which of the following statements is/are true for a 0.10 M solution of a weak acid HA?

a. [ H+] >> [ A−]

b. [ H+] = [ A−]

c. The pH is 1.00.

d. The pH is less than 1.00.

Answer:

b. [ H+] = [ A−]

Explanation:

Given the acid as HA, we know that being a weak acid, its dissociation in water can never be 100%. If it were a strong acid, then it could have undergone a 100% dissociation in solution. The conjugate base of a weak acid is a always a weak base hence A^- is expected to act as a weak base. At the same concentration, weak acids have a higher pH value than strong acids. Hence if the pH of a strong acid HA is 1, then the pH of a weak acid HA must be greater than 1.

But, we look at the equation for the dissociation of the weak acid HA

HA(aq)⇄H^-(aq) + A^-(aq). This implies that the HA dissociates in a 1:1 ratio therefore; [H+] = [ A−], hence the answer given above.

The balanced redox reaction is PbO2+2I-+4H+---Pb2+ +I2+4H2O and the number of OH- in the final balanced equation is 4

The two Half Cell reactions are as,

Reduction:                   PbO₂  +  2e⁻   →     Pb²⁺  

As it is a medium acidic reaction, so add H⁺ on the reactant side as it has more number of oxygen atoms and add OH- on the product side, and balance the elements, So,

                            4 H⁺     +   PbO₂  +  2e⁻   →     Pb²⁺   +    4OH-     (1)

Oxidation:                        I⁻     →     I₂   +  1e⁻

Balance the Number of elements along with electrons,

  2 I⁻     →     I₂   +  2e⁻                                    (2)

Compare eq. 1 and 2,

                            4 H⁺     +   PbO₂  +  2e⁻   →     Pb²⁺   +    4OH-

                                                          2 I⁻     →     I₂   +  2e⁻

                           ⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻

                           PbO₂  +  2 I⁻  +  4 H⁺     →     Pb²⁺  +  I₂  + 4OH-

The number of OH- ions is 4

To learn more about redox reaction visit:

brainly.com/question/13293425

#SPJ9

Answer:

C: francium-221

Explanation:

First of all to get a broader perspective, every isotope of francium usually undergoes decay to form astatine, radium, or radon.

Now, Francium-223 and francium-221 are it's only isotopes that occur in nature.

However, francium-221 is the one that undergoes alpha decay to produce astatine-217.

The quantity of the product obtained from the reaction is generally expressed in terms of the yield of the reaction. The amount obtained actually is called the actual yield.

The amount of the product which is predicted by the stoichiometry is called the theoretical yield. A reaction yield is reported as the percentage of the theoretical amount.

The percentage yield is the ratio of actual yield to the theoretical yield.

% yield = Actual yield / Theoretical yield × 100

a. Molar mass of PbCO₃ = 267.21 g/mol

Molar mass of PbCl₂ = 278.1 g/mol

2.871 g of PbCO₃ gives:

2.871 × 278.1 / 267.21 = 2.988 g  PbCl₂

b. % yield = 2.385 / 2.988 × 100 = 79.82 %

Thus the theoretical yield is 2.988 g and the % yield is 79.82 %.

To know more about % yield , visit;

https://brainly.com/question/29714892

#SPJ1

Answer:

Density is m/V. Also, 1 liter = 1000 . So, we get 0.890/(5*1000) = g/cm^3. You can convert this to kg/m^3 as well by multiplying it by 10. Depends which one you want.

H3O+ is the strongest acid and OH− is the strongest base that can exist in equilibrium with H₂O.

A reversible chemical reaction is said to be in chemical equilibrium when there is no net change in the quantity of reactants or products. When a chemical reaction is reversible, the products is react with the original reactants as soon as they are created.

We may get a sense of where the equilibrium is by using the equilibrium constant. The closer the equilibrium is to the products, the larger the equilibrium constant.

To know more about Equilibrium visit:

https://brainly.com/question/7145687

#SPJ9

The  most probable values for the first four ionization energies of the aluminum are : IE₁ = 578 kJ/mol, IE₂ = 1817 kJ/mol, "IE₃ = 2745 kJ/mol", IE₄ = 11577 kJ/mol.

The ionization energy is the amount of the energy required to remove the electron from an atom. The electronic configuration of Al is given as :

Al electronic configuration = 1s² 2s² 2p⁶ 3s² 3p¹. The fourth ionization energy is comparatively high because the 2p subshell is fully filled and the energy required to remove the electron from the stable electronic configuration will be high. Therefore, the fourth ionization energy is high.

To learn more about ionization energy here

https://brainly.com/question/29629534

#SPJ4

The combustion of wood results in the generation of new substances such as carbon dioxide gas, water vapor, ash, and so on. Some compounds do not completely burn or do not react at all, resulting in the formation of fire ash.

When we burn wood, it transforms into ashes, a new material, and the process is irreversible, resulting in a chemical shift. No new material is generated while chopping the wood into little pieces. It is a bodily transformation. When two colorless liquids are put together, the creation of a solid precipitate indicates the presence of a chemical reaction. When a colorless solution of lead(II) nitrate is added to a colorless solution of potassium iodide, an immediate yellow solid known as a precipitate is formed. Dense hardwood species, such as maple and oak, contain more energy, burn hotter and slower, and release more heat, resulting in longer-lasting fires and coal beds. Because softwoods are less thick than hardwoods, they burn quicker in short-lived flames.

Learn more about potassium from here;

https://brainly.com/question/13321031

#SPJ4

The Correct electron configuration of carbon as 1s² 2s² 2p². Option B.

To understand why this is the correct electron configuration, let's break it down step by step:

The atomic number of carbon is 6, which means it has six electrons. Electrons are distributed in energy levels or shells around the nucleus.

The first shell, known as the 1s orbital, can hold a maximum of 2 electrons. Therefore, the first part of the electron configuration is 1s², indicating that two electrons occupy the 1s orbital.

The second shell has two subshells: the 2s orbital and the 2p orbital. The 2s orbital can hold a maximum of 2 electrons, while the 2p orbital can hold a maximum of 6 electrons. In the case of carbon, after the 1s orbital, two more electrons occupy the 2s orbital. So far, we have 1s² 2s².

The remaining two electrons in carbon are placed in the 2p orbital. The 2p orbital consists of three separate p orbitals: 2px, 2py, and 2pz. Each p orbital can hold a maximum of 2 electrons. Therefore, the last part of the electron configuration for carbon is 2p², indicating that two electrons occupy the 2px and 2py orbitals. Option B is correct.

For more such question on electron. visit :

https://brainly.com/question/28420589

#SPJ8

Answer:

1. pure water and salt mixture is first heated until salt appears then the mixture is poured using filter paper.

Answer:

\(\large \boxed{\text{1.4 mol/L}}\)

Explanation:

(a) Balanced equation

2NaOH + H₂SO₄ ⟶ Na₂SO₄ + 2H₂O  

(b) Moles of H₂SO₄

\(\text{Moles of H$_{2}$SO}_{4} = \text{32.5 mL H$_{2}$SO}_{4} \times \dfrac{\text{1.0 mmol H$_{2}$SO$_{4}$}}{\text{1 mL H$_{2}$SO$_{4}$}}\\= \text{32.5 mmol H$_{2}$SO}_{4}\)

(c) Moles of NaOH

The molar ratio is 2 mol NaOH:1 mol H₂SO₄.

\(\text{Moles of NaOH} = \text{32.5 mmol H$_{2}$SO}_{4} \times\dfrac{\text{2 mmol NaOH}}{\text{1 mmol H$_{2}$SO}_{4}}\\\\= \text{65 mmol NaOH}\)

(d) Molar concentration of NaOH

\(c = \dfrac{\text{moles of solute}}{\text{litres of solution}}\\\\c = \dfrac{n}{V}\\\\c= \dfrac{\text{65 mmol}}{\text{45.0 mL}} = \text{1.4 mol$\cdot$L$^{-1}$}\\\\\text{The molar concentration of the NaOH is $\large \boxed{\textbf{1.4 mol/L}}$}\)

Note: The answer can have only two significant figures because that is all you gave for the molar concentration of the sulfuric acid.

Answer:

Explanation:

See  attached file .

The number of possible isomers of Bromodimethylbenze are 6. One of the isomers is 2 Bromo - m -xylene. The number of possible isomers of an aromatic compound \(\rm C_7H_8O\)  are 5. One of these isomers has been o - cresol.

(a). Bromodimethylbenze has also been known as bromoxylene. The compound has been consisted of 1 benzene ring with 2 methyl groups and a bromine atom.

The possible isomers of bromoxylene are:

(b). Aromatic compound with formula \(\rm C_7H_8O\) has been the benzene compound. The compound has been consisted of a benzene ring with 1 methyl group and oxygen atom.

The possible isomers of  \(\rm C_7H_8O\) are:

Thus, the number of possible isomers of Bromodimethylbenze are 6. One of the isomers is 2 Bromo - m -xylene. The number of possible isomers of an aromatic compound \(\rm C_7H_8O\)  are 5. One of these isomers has been o - cresol.

For more information about isomers, refer to the link:

https://brainly.com/question/12796779

The balanced chemical equation for the reaction is:

2NaOH(aq) + FeCl₂(aq) --> 2NaCl(aq) + Fe(OH)₂(s)

Chemical equations are representations of chemical reactions using symbols and formula of the reactants and products.

The reactants are located on the left side while the products are located on the right side.

Reactants —> Products

The balancing of chemical equations follows the law of conservation of matter which states that matter can neither be created nor destroyed during a chemical reaction but can be transferred from one form to another.

Sodium hydroxide => NaOH

Iron (II) chloride => FeCl₂

2NaOH(aq) + FeCl₂(aq) --> 2NaCl(aq) + Fe(OH)₂(s)

Learn more about chemical equation:

https://brainly.com/question/7181548

#SPJ1

the spin quantum number has values+1212 of -1212 describes the trends in ionic size.

spin quantum is denoted by (s) as it represents the electronic configuration of the atom and the ionic size also depends on the electronic configuration of the sub-shells of the atom like l, m, n, s.

ionic size increases as the electronic configuration increases because the electron adds as we move up to a higher atomic number

all the other quantum numbers may vary from atom to atom but the spin quantum number remains either +1212 or -1212. it also describes the orientation of the electrons in an atom and the axis of electrons in an atom.

learn more about quantum number here;

https://brainly.com/question/2292596

#SPJ4

Answer:

P₂O₅

Hope it helps.

Plzzz can you give me brainliest.

Answer:

hope this answer will help you

Explanation:

we can simply do this by unitary method

22.4L is requires or 1 mole of oxygen gas

54L requires 1/22.4×54 = 2.41 moles

we know that no. of moles =mass/mol.mass

in order to get mass we multiply moles by mol. mass

2.41×32=77.1g

so, the correct option is

Answer:

Na F

Explanation:

because electrovalent bond is present between them

From the calculations, the change in energy is - 190 J.

From the first law of thermodynamics, the energy is neither created nor destroyed but is transformed from one form to another.

From the law;

U = q + w

U = internal energy

q = heat

w = work

Since work is done on the surroundings and the gas absorbs heat then;

U = 132 J - 322 J

U = - 190 J

Learn more about thermodynamics:https://brainly.com/question/1368306

#SPJ1

option a,b,c are correct.gather your belongings,turn off all hot plates & other heating apparatus, turn off all water these are options that must be done in case of a fire alarm or other evacuation .

To guarantee your safety, take prompt action when the fire alarm goes off. The fire alarm system was created and constructed to give you a head start so you may safely leave the building in an emergency.Never dismiss a warning or believe it to be fake or the outcome of a test.The nearest and safest exit and/or stairs must be used by everyone to leave the building.Never leave during a fire alarm activation in an elevator.Once outside, make your way away from the structure. Gather on the sidewalk of the building next door or across the street.The firefighters and fire engines will be working in front of the structure. Don't stand in their way as they enter the building.

learn more about heating Refer:/brainly.com/question/11737047

#SPJ4

There are approximately 0.3392 grams of oxygen and 0.00088 grams of carbon dioxide in a single breath of fresh air.

What is Concentration?

In chemistry, concentration refers to the amount of a substance (solute) that is present in a given volume or mass of another substance (solvent). It is a measure of how much of a particular substance is present in a mixture, solution, or sample.

The concentration of gases in fresh air is approximately 21% oxygen, 0.04% carbon dioxide, and 1-2% water vapor.

To calculate the number of moles of oxygen and carbon dioxide in a breath of fresh air, we need to use the ideal gas law:

PV = nRT

where P is the pressure of the gas, V is its volume, n is the number of moles, R is the gas constant, and T is the temperature in Kelvin.

Let's assume that the volume of a single breath of fresh air is 0.5 L at room temperature (25°C or 298 K) and atmospheric pressure (1 atm). We can then use the ideal gas law to calculate the number of moles of oxygen and carbon dioxide:

For oxygen:

PV = nRT

n = PV/RT = (1 atm)(0.21)(0.5 L)/(0.08206 L·atm/mol·K)(298 K) = 0.0106 mol

For carbon dioxide:

PV = nRT

n = PV/RT = (1 atm)(0.0004)(0.5 L)/(0.08206 L·atm/mol·K)(298 K) = 0.00002 mol

So there are approximately 0.0106 moles of oxygen and 0.00002 moles of carbon dioxide in a single breath of fresh air.

To calculate the mass of each gas, we can use the molar mass of each gas:

Using the number of moles we calculated above, we can calculate the mass of each gas:

Mass of oxygen = number of moles x molar mass = 0.0106 mol x 32 g/mol = 0.3392 g

Mass of carbon dioxide = number of moles x molar mass = 0.00002 mol x 44 g/mol = 0.00088 g

So there are approximately 0.3392 grams of oxygen and 0.00088 grams of carbon dioxide in a single breath of fresh air.

It's worth noting that the concentration of gases in exhaled air can vary depending on a number of factors, including the individual's health status, activity level, and surrounding environment.

Learn more about Concentration from given link

https://brainly.com/question/17206790

#SPJ4

Answer:

5.63 g

Explanation:

Step 1: Write the balanced equation

CuBr₂(aq) + 2 AgCH₃CO₂(aq)  ⇒  2 AgBr(s) + Cu(CH₃CO₂)₂(aq)

Step 2: Calculate the reacting moles of copper (II) bromide

30.0 mL of 0.499 M CuBr₂ react. The reacting moles of CuBr₂ are:

\(0.0300L \times \frac{0.499mol}{L} = 0.0150mol\)

Step 3: Calculate the moles formed of silver (I) bromide

The molar ratio of CuBr₂ to AgBr is 1:2. The moles formed of AgBr are 2/1 × 0.0150 mol = 0.0300 mol.

Step 4: Calculate the mass corresponding to 0.0300 mol of AgBr

The molar mass of AgBr is 187.77 g/mol.

\(0.0300 mol \times \frac{187.77g}{mol} = 5.63 g\)

Answer:

The cell potential for the given galvanic cell is 0.188 V.

Explanation:

To calculate the cell potential, we can use the Nernst equation:

Ecell = E°cell - (RT/nF)ln(Q)

where E°cell is the standard cell potential, R is the gas constant (8.314 J/mol·K), T is the temperature in Kelvin (25°C = 298 K), n is the number of moles of electrons transferred (in this case, n = 2), F is the Faraday constant (96,485 C/mol), and Q is the reaction quotient.

First, we need to write the half-reactions and their standard reduction potentials:

Sn4+(aq) + 2e- → Sn2+(aq) E°red = 0.15 V

Fe3+(aq) + e- → Fe2+(aq) E°red = 0.77 V

The overall reaction is the sum of the half-reactions:

Sn2+(aq) + 2Fe3+(aq) → Sn4+(aq) + 2Fe2+(aq)

The reaction quotient Q can be expressed as:

Q = [Sn4+][Fe2+]^2 / [Sn2+][Fe3+]^2

Substituting the given concentrations, we get:

Q = (0.00655)(0.01139)^2 / (0.0624)(0.0437)^2 = 0.209

Now we can calculate the cell potential:

Ecell = 0.15 V + 0.0592 V log([Fe2+]^2/[Fe3+]) + 0.0592 V log([Sn4+]/[Sn2+])

= 0.15 V + 0.0592 V log(0.01139^2/0.0437^2) + 0.0592 V log(0.00655/0.0624)

= 0.188 V

Therefore, the cell potential for the given galvanic cell is 0.188 V.

The cell potential for the given galvanic cell in which the given reaction occurs at 25 °C is 0.188 V.

To find the cell potential, we take the Nernst equation:

Ecell = E°cell - (RT/nF)ln(Q)

In which R is the gas constant (8.314 J/mol·K) and E° cell is the standard cell potential.

T temperature in Kelvin (25°C = 298 K), and n is the number of moles of electrons transferred (n = 2), Q is the reaction quotient and F is the Faraday constant (96,485 C/mol).

Firstly, write the half-reactions and then their standard reduction potentials:

Sn⁴⁺(aq) + 2e⁻  → Sn²⁺(aq) E°red = 0.15 V

Fe³⁺(aq) + e⁻ → Fe²⁺(aq) E°red = 0.77 V

The overall reaction is the sum of the half-reactions:

Sn²⁺(aq) + 2Fe³⁺(aq) → Sn⁴⁺(aq) + 2Fe²⁺(aq)

The Q reaction quotient can be written as:

Q = [Sn⁴⁺][Fe²⁺]² ÷ [Sn²⁺][Fe²⁺]²

Substituting the given concentrations, we observe:

Q = (0.00655)(0.01139)² ÷ (0.0624)(0.0437)² = 0.209

Next, we can find the cell potential:

Ecell = 0.15 V + 0.0592 V log([Fe²⁺]²/[Fe³⁺]) + 0.0592 V log([Sn⁴⁺]/[Sn²⁺])

= 0.15 V + 0.0592 V log(0.01139²÷0.0437²) + 0.0592 V log(0.00655÷0.0624)

= 0.188 V

Thus, the cell potential for the given galvanic cell is 0.188 V.

Learn more about cell potential, here:

https://brainly.com/question/29719917

#SPJ2

Answer:

thete are 672 seeds in 14 kg