Answer:
Tin
Explanation:
Metals are mostly solid at room temp, solid, good conductors of heat, and malleable. The only metal on this list is tin.
- Hope that helps! Please let me know if you need further explanation.
The element that student observing is Tin
Information regarding metal is as follows:
Metals should be considered as solid at room temperature, solid at good conductors of heat, and malleable. The only metal on this list is tin.So, that means, the sulfur, silicon, and the carbon is not the metal.Find out more information about the metal here: https://brainly.com/question/16759172?referrer=searchResults
what is the reaction?
Answer:
A chemical reaction is a process in which one or more substances, also called reactants, are converted to one or more different substances, known as products. ... A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
Explanation:
Hopefully this is what you needed
For a school event 1/6 of the athletic field is reversed for the fifth -grade classes the reserved part of the field is divided equally Among the 4 fifth grade classes in the school what fraction of the whole athletic field is reserved for each fifth class
Answer:
[tex]\frac{1}{24}[/tex]
Explanation:
Given:
For a school event, 1/6 of the athletic field is reserved for the fifth -grade classes and the reserved part of the field is divided equally among the 4 fifth grade classes in the school.
To find: fraction of the whole athletic field reserved for each fifth class
Solution:
Fraction of the whole athletic field reserved for four fifth classes = [tex]\frac{1}{6}[/tex]
So, fraction of the whole athletic field reserved for each fifth class = [tex]\frac{1}{4}(\frac{1}{6})=\frac{1}{24}[/tex]
Dysphagia is the name of a disorder that disrupts
А
the swallowing reflex
B
the absorption of essential nutrients
acid levels in the stomach
C
D
the stomach lining
Answer:
A. The Swallowing reflex
Explanation:
Dysphagia Is a a condition that makes swallowing difficult.
PbCl2+ AgNO3------>Pb(NO3)2+ AgCl
Decomposition
Synthesis
Double displacement
Exothermic
Answer:
Option C
Explanation:
A double displacement reaction is the one in which two chemical compounds having a cation and anion in each exchange their positive and negative ions thereby forming new compounds or products.
Here,
The first compound [tex]PbCl_2[/tex] has a positive ion [tex]Pb[/tex] and negative ion [tex]Cl^-[/tex]
Like wise the second compound [tex]Ag(NO_3)[/tex] has a positive ion [tex]Ag[/tex] and negative ion [tex]NO_3[/tex]
The new compounds will be formed when cation of one compound attaches with the anion of other compound. Hence the new compounds are
[tex]Pb(NO_3)_2[/tex]
[tex]AgCl[/tex]
This is example of double displacement reaction.
Option C is correct
If you collect 1.75 L of hydrogen gas during a lab experiment, when the room temperature is 23ºC and the barometric pressure is 105 kPa, how many moles of hydrogen will you have?
Answer:
[tex]n=0.0747mol[/tex]
Explanation:
Hello,
In this case, since we can consider hydrogen gas as an ideal gas, we check the volume-pressure-temperature-mole relationship by using the ideal gas equation:
[tex]PV=nRT[/tex]
Whereas we are asked to compute the moles given the temperature in Kelvins, thr pressure in atm and volume in L as shown below:
[tex]n=\frac{105kPa*\frac{0.009869atm}{1kPa}*1.75L}{0.082\frac{atm*L}{mol*K}*(23+273.15)K} \\\\n=0.0747mol[/tex]
Best regards.
1. A substance that gets dissolved to create a solution is best described as to
as
Answer:
Solute
Explanation
A substance that gets dissolved to create a solution is best described as to as
2. What happens to the pH when you add more H+ ions to a solution that has no buffers?
it takes 26.23 mL of a 1.008 M NaOh solution to neutralize a solution of an unknown monoprotic acid in 150.2 mL of solution. What is the molarity of the unknown?
Answer:
.176 M
Explanation:
set the number of moles of the base equal to the number of moles of acid.
(1.008 mol/L)(26.23 x 10^-3 L)=(150.2x10^-3 L)(x)
x = .176030892 mol/L
What is the hydrogen ion concentration [H+] of a HCl solution if the pH is measured to be 2.0?
Answer:
.01
Explanation:
H30+=10^-pH
- Hope that helps! Please let me know if you need further explanation.
6.) (5 points) Assume you have a system with a fixed pH of 4.0. It is well buffered and therefore the pH will not change. What is the predominant state of a molecule with a dissociable proton with a pKa of 5.2 if it is introduced to that system (protonated or deprotonated)
Answer:
Dissociated state is the predominant one
Explanation:
When a molecule with pKa of 4.52 is in an aqueous solution at pH = 4.0, follows the H-H equation, thus:
pH = pKa + log₁₀ [A⁻] / [HA]
Where [A⁻] is the dissociated state and [HA] represents the protonated state
Replacing:
4.0 = 5.2 + log₁₀ [A⁻] / [HA]
-1.2 = log₁₀ [A⁻] / [HA]
0.063 = [A⁻] / [HA]
[HA] = 16 [A⁻]
That means you have 16 times more [HA] than [A⁻] and the dissociated state is the predominant one
The roles of hydrochloric acid (HCl) in the digestive system?
Answer:
There are several roles of HCl in the digestive system. Some of them are as follows:
There is HCl present in the gastric juice of your stomach, otherwise known as stomach acid. The acidic nature of the HCl in the stomach acid make it useful for quickly breaking down food.HCl's acidic nature also allows it to kill bacteria and other pathogens that you may have ingested, keeping you safe from their dangerous effects.HCl can also contribute Hydrogen ions, which helps to activate pepsinogen, a substance secreted by the stomach wall. The activated pepsinogen is then converted into pepsin, which aids in the digestion of proteins. Because of this, HCl essentially keeps the systems of protein digestion in check. Too much or too little of it can be dangerous.HCl also makes sure that vitamins are properly absorbed and acts as a communicator to other organs in the digestive system.10. When the pressure on a gas inetcases three times, by how much will the volume incrcase or decrease?
Answer:The answer to this question comes from experiments done by the scientist Robert Boyle in an effort to improve air pumps. In the 1600's, Boyle measured the volumes of gases at different pressures. Boyle found that when the pressure of gas at a constant temperature is increased, the volume of the gas decreases. when the pressure of gas is decreased, the volume increases. this relationship between pressure and volume is called Boyle's law.
Explanation: So, at constant temperature, the answer to your answer is: the volume decreases in the same ratio as the ratio of pressure increases.
BUT, in general, there is not a single answer to your question. It depend by the context.
For example, if you put the gas in a rigid steel tank (volume is constant), you can heat the gas, so provoking a pressure increase. But you won't get any change in volume.
Or, if you heat the gas in a partially elastic vessel (as a tire or a soccer ball) you will get both an increase of volume AND an increase of pressure.
FINALLY if you inflate a bubblegum ball, the volume will be increased without any change in pressure and temperature, because you have increased the NUMBER of molecules in the balloon.
There are many other ways to change volume and pressure of a gas that are different from the Boyle experiment.
When Mrs. Green describes the physical properties of matter she said that physical properties often concern changes in state, One
physical property that does not describe a change in state is
A)
density
B)
evaporation
C)
freezing
D)
melting
Answer:
density
Explanation:
Density is an important measurement. It has an unit: g/mL or kg/L, ...
Evaporation, freezing, melting are the processes in which the substances change their states. Other processes are: condensation, sublimation, deposition.
...
Hope this answer can help you. Have a nice day!
A solution is prepared by mixing 525 mL of ethanol with 597 mL of water. The molarity of ethanol in the resulting solution is 8.35 M. The density of ethanol at this temperature is 0.7893 g/mL. Calculate the difference in volume between the total volume of water and ethanol that were mixed to prepare the solution and the actual volume of the solution. g
Answer:
[tex]\Delta V = 234.736\,mL[/tex]
Explanation:
The quantity of moles of ethanol in the solution is:
[tex]n_{C_{2}H_{5}OH} = \left(\frac{597\,mL}{1000\,mL} \right)\cdot \left(8.35\,\frac{mol}{L} \right)[/tex]
[tex]n_{C_{2}H_{5}OH} = 4.985\,mol[/tex]
The mass and volume of ethanol in the solution are, respectively:
[tex]m_{C_{2}H_{5}OH} = (4.985\,mol)\cdot \left(46.07\,\frac{g}{mol} \right)[/tex]
[tex]m_{C_{2}H_{5}OH} = 229.658\,g[/tex]
[tex]V_{C_{2}H_{5}OH} = \frac{229.658\,g}{0.7893\,\frac{g}{mL} }[/tex]
[tex]V_{C_{2}H_{5}OH} = 290.964\,mL[/tex]
The difference between the total volume of water and ethanol mixed to prepare the solution and the actual volume of solution is:
[tex]\Delta V = (525\,mL+597\,mL) - (597\,mL + 290.964\,mL)[/tex]
[tex]\Delta V = 234.736\,mL[/tex]
The difference in volume between the total volume of water and ethanol is ΔV =234.736 mL.
Calculation for moles of ethanol:The quantity of moles of ethanol in the solution is:
[tex]nC_2H_5OH=\frac{597mL}{1000mL} *8.35mol/L\\\\nC_2H_5OH=4.985 moles[/tex]
The mass and volume of ethanol in the solution are, respectively:
[tex]mC_2H_5OH=4.985moles*46.07g/mol\\\\mC_2H_5OH=229.685g[/tex]
[tex]VC_2H_5OH=\frac{229.685g}{0.7893g/mL} \\\\VC_2H_5OH=290.964mL[/tex]
The difference between the total volume of water and ethanol mixed to prepare the solution and the actual volume of solution is:
ΔV= (525mL+597mL)- (597mL + 290.964 mL)
ΔV= 234.736mL
Find more information about Moles here:
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Metamorphic rocks directly form from
Answer:
Metamorphic rocks are formed from pre-existing rock and sediment materials. They are formed when igneous, sedimentary, or other pre-existing metamorphic rocks are exposed to the heat and pressure as well as super-heated mineral-rich fluids. They are compacted together to form a new rock altogether. Metamorphism does not include the melting or liquefaction of the pre-existing rock. Instead, it compacts them and crushes them, pushing them together at extreme heat and pressure to form a new rock altogether composed of sedimentary, igneous, and other metamorphic rock. It's the rock hybrid of the geologic world.
Metamorphism is similar to when you squish playdough together, it doesn't form a new playdough color (unless you REALLY mixed that poor playdough together). It forms an amalgamation of different colors and patterns made from the other rock.
Taken from a paper I once wrote I explained this again:
"Metamorphic rocks are formed when pre-existing rocks and their minerals are compressed and altered by Earth’s internal processes; interior pressure, temperature (heat), and chemical reactions. The minerals and pre-existing rock necessary for the creation of metamorphic rock must then also be located deep underground if such processes are expected to make an impact and create a metamorphic rock."
Help me 6th grade science !:))
Answer:
I believe it is C.Shelter.
Answer:
C
Explanation:
The butterflies use the trees for shelter, because the trees protect them from the weather and the cold air.
Which diagram correctly describes the changes that occur as a small piece of rock falls from space and hits the earth
Answer:
the motion of gravity
Explanation:
Answer:
its c
Explanation
advhuosijoklxcmnjdabsuhggggabciaciudeifweingivg eygerigsygfe97rsghisdcvhbsduigwiugfu9uigdgiurfgyisdgfsdgfegiygewifgsdygfewusgfuyesigf7wgfiesgfiusgdfies
Glycolysis is the process by which energy is harvested from glucose by living things. Several of the reactions of glycolysis are thermodynamically unfavorable (nonspontaneous), but proceed when they are coupled with other reactions.
Reaction A: Pi+glucose⟶glucose-6-phosphate+H2OΔG=13.8 kJ/mol
Reaction B: Pi+fructose-6-phosphate⟶fructose-1,6-bisphosphate+H2OΔG=16.3 kJ/mol
Reaction C: ATP+H2O⟶ADP+PiΔG=−30.5 kJ/mol
Select every unfavorable reaction.
reaction B
reaction C
reaction A
Select every set of coupled reactions where the overall reaction is favorable.
reactions B and C
reactions A and B
reactions A and C
What is the net change in free energy if one set of reactions from the previous question is coupled so that the overall reaction is favorable? Note that if you selected more than one set of coupled reactions as favorable in the previous question, you may enter the net change for any one of your selected sets.
Answer:
Unfavorable reactions: Reaction A and Reaction B.
Coupled reactions favorable: Reactions B and C and Reactions A and C.
Net change:
Reactions B and C : -14.2kJ/mol
Reactions A and B : 30.1kJ/mol
Reactions A and C: -16.7kJ/mol
Explanation:
A reaction is thermodynamically favorable (spontaneous) if ΔG < 0. Thus, the unfavorable reactions -ΔG > 0- are:
Reaction A and reaction B.
When reaction C is coupled with reaction B and reaction A the chemical equation is:
ATP + fructose-1,6-phosphate ⟶ ADP + fructose-1,6-bisphosphate
ΔG = 16.3 - 30.5 = -14.2 kJ/mol
ATP + glucose ⟶ ADP + glucose-6-phosphate
ΔG = 13.8 - 30.5 = -16.7 kJ/mol
The coupled reaction of A and B has a change in free energy of:
ΔG = 13.8 + 16.3 = 30.1 kJ/mol
Claims • Evidence • Reasoning Make
a claim about ways people can stay safe
during storms with high wind and heavy
rains. Summarize evidence to support the
claim and explain your reasoning.
Answer:
the claim is that when people avoid storms they hide in any secret place in there house
Explanation:
when people do that they don't even have to worry about a single thing that will happen to them
If a mineral isn't scratched by a fingernail, what can you conclude about the minerals
hardness?
It is at least a hardness of 4.0
A mineral can't be tested by a fingernail.
The hardness is more than 2.5.
The hardness is less than 2.5.
Answer:
The hardness is more than 2.5. Hope this helps.
Answer:
The hardness is more than 2.5.
Explanation:
using the following balanced chemical equation: PCL5 -> PCL3 + CL2 and knowing that Keq = 7.9, [PCL3] = 0.054M and [CL2] = 0.34M
a. write the Keq expression for the reaction
b. find the [PCL5]
c circle the correct answer: the reaction favored is the (forward, reverse)
Answer:
see explanations
Explanation:
PCl₅ => PCl₃ + Cl₂
C(eq): [PCl₅] 0.054M 0.34M
a. Keq = [PCl₃][Cl₂]/[PCl₅]
b. 7.9 = (0.054)(0.34)/[PCl₅] => [PCl₅] = (0.054)(0.34)/(7.9) = 0.0023M
c. If [PCl₃] = 0.054M; [Cl₂] = 0.34M and [PCl₅] = 0.0023M then the reaction is at equilibrium and will not shift forward or in reverse. In order to determine if reaction is not at equilibrium, a set of concentration values needs to be given in problem, used to calculate Qeq and compared to the given Keq value. The following defines direction of shift ...
Keq < Qeq => rxn shifts left
Keq = Qeq => rxn is at equilibrium (no shift)
Keq > Qeq => rxn shifts right
NOTE: If Keq is listed first followed by Qeq in the above conditions, the inequality symbol indicates direction of shift.
At what temperature will a gas be, if you allow it to expand from its original volume of 756 mL at 65.0 °C to 1.40 L? (hint volume needs to be the same)
Answer:
120.4 gradius Celcius
Explanation:
Please see the step-by-step solution in the picture attached below.
Hope this answer can help you. Have a nice day!
A 99.8 mL sample of a solution that is 12.0% KI by mass (d: 1.093 g/mL) is added to 96.7 mL of another solution that is 14.0% Pb(NO3)2 by mass (d: 1.134 g/mL). How many grams of PbI2 should form?
Pb(NO3)2(aq) + 2 KI(aq) PbI2(s) + 2 KNO3(aq)
Answer:
[tex]m_{PbI_2}=18.2gPbI_2[/tex]
Explanation:
Hello,
In this case, we write the reaction again:
[tex]Pb(NO_3)_2(aq) + 2 KI(aq)\rightarrow PbI_2(s) + 2 KNO_3(aq)[/tex]
In such a way, the first thing we do is to compute the reacting moles of lead (II) nitrate and potassium iodide, by using the concentration, volumes, densities and molar masses, 331.2 g/mol and 166.0 g/mol respectively:
[tex]n_{Pb(NO_3)_2}=\frac{0.14gPb(NO_3)_2}{1g\ sln}*\frac{1molPb(NO_3)_2}{331.2gPb(NO_3)_2} *\frac{1.134g\ sln}{1mL\ sln} *96.7mL\ sln\\\\n_{Pb(NO_3)_2}=0.04635molPb(NO_3)_2\\\\n_{KI}=\frac{0.12gKI}{1g\ sln}*\frac{1molKI}{166.0gKI} *\frac{1.093g\ sln}{1mL\ sln} *99.8mL\ sln\\\\n_{KI}=0.07885molKI[/tex]
Next, as lead (II) nitrate and potassium iodide are in a 1:2 molar ratio, 0.04635 mol of lead (II) nitrate will completely react with the following moles of potassium nitrate:
[tex]0.04635molPb(NO_3)_2*\frac{2molKI}{1molPb(NO_3)_2} =0.0927molKI[/tex]
But we only have 0.07885 moles, for that reason KI is the limiting reactant, so we compute the yielded grams of lead (II) iodide, whose molar mass is 461.01 g/mol, by using their 2:1 molar ratio:
[tex]m_{PbI_2}=0.07885molKI*\frac{1molPbI_2}{2molKI} *\frac{461.01gPbI_2}{1molPbI_2} \\\\m_{PbI_2}=18.2gPbI_2[/tex]
Best regards.
Answer:
Mass PbI2 = 18.19 grams
Explanation:
Step 1: Data given
Volume solution = 99.8 mL = 0.0998 L
mass % KI = 12.0 %
Density = 1.093 g/mL
Volume of the other solution = 96.7 mL = 0.967 L
mass % of Pb(NO3)2 = 14.0 %
Density = 1.134 g/mL
Step 2: The balanced equation
Pb(NO3)2(aq) + 2 KI(aq) ⇆ PbI2(s) + 2 KNO3(aq)
Step 3: Calculate mass
Mass = density * volume
Mass KI solution = 1.093 g/mL * 99.8 mL
Mass KI solution = 109.08 grams
Mass KI solution = 109.08 grams *0.12 = 13.09 grams
Mass of Pb(NO3)2 solution = 1.134 g/mL * 96.7 mL
Mass of Pb(NO3)2 solution = 109.66 grams
Mass of Pb(NO3)2 solution = 109.66 grams * 0.14 = 15.35 grams
Step 4: Calculate moles
Moles = mass / molar mass
Moles KI = 13.09 grams / 166.0 g/mol
Moles KI = 0.0789 moles
Moles Pb(NO3)2 = 15.35 grams / 331.2 g/mol
Moles Pb(NO3)2 = 0.0463 moles
Step 5: Calculate the limiting reactant
For 1 mol Pb(NO3)2 we need 2 moles KI to produce 1 mol PbI2 and 2 moles KNO3
Ki is the limiting reactant. It will completely be consumed ( 0.0789 moles). Pb(NO3)2 is in excess. There will react 0.0789/2 = 0.03945 moles. There will remain 0.0463 - 0.03945 = 0.00685 moles
Step 6: Calculate moles PbI2
For 1 mol Pb(NO3)2 we need 2 moles KI to produce 1 mol PbI2 and 2 moles KNO3
For 0.0789 moles KI we'll have 0.0789/2 = 0.03945 moles PbI2
Step 7: Calculate mass of PbI2
Mass PbI2 = moles PbI2 * molar mass PbI2
Mass PbI2 = 0.03945 moles * 461.01 g/mol
Mass PbI2 = 18.19 grams
An aqueous solution of HNO2 is poured onto a solid pile of SrCO3. Identify the net ionic equation for this reaction.
A) SrCO3(s) + 2 HNO2(aq) → Sr(NO2)2(aq) + HCO3(aq)
B) no reaction occurs
C) Sr2+ + CO32- + 2 H+ → Sr2+ + H2O + CO2(g)
D) SrCO3(s) + 2 HNO2(aq) → Sr(NO2)2 + H2O + CO2(g)
E) SrCO3(s) + 2 H+ → Sr2+ + H2O + CO2(g)
Answer:
D) SrCO3(s) + 2 HNO2(aq) → Sr(NO2)2 + H2O + CO2(g)
Explanation:
When an acid react with carbonate, it produces nitrate, carbon-dioxide gas and water molecule. When nitrous acid react with Strontium carbonate, three products are formed i. e. Strontium nitrate, carbon-dioxide gas and water. In the reaction, both nitrous acid and Strontium carbonate exchange their partners with each other and forming a different products.
Answer:
Option E is correct.
The net ionic equation is given as
SrCO₃(s) + 2H⁺ → Sr²⁺ + H₂O + CO₂(g)
Explanation:
When acids react with carbonate compounds, it leads to the liberation of CO₂, hence, when an aqueous solution of HNO₂ is poured onto a solid pile of SrCO₃, the balanced overall equation is given as
SrCO₃(s) + 2HNO₂(aq) → Sr(NO₂)₂ + H₂O + CO₂(g)
But for the net ionic reaction, it is obtained by eliminating ions that occur on both sides of the overall reaction. Note that ions exist onlubone the aqueous compounds.
Hence, the two aqueous compounds that exist in the balanced overall equation are
2HNO₂(aq) on the left hand side and Sr(NO₂)₂ on the right hand side
In their ionic form, 2HNO₂ ⇌ 2H⁺ + 2NO₂⁻
And Sr(NO₂)₂ ⇌ Sr²⁺ + 2NO₂⁻
And it is evident that the ion that occurs on both sides and needs to be deleted is NO₂⁻,
Hence, the net ionic equation is
SrCO₃(s) + 2H⁺ → Sr²⁺ + H₂O + CO₂(g)
Hope this Helps!!!
A molecule of which compound has a multiple covalent bond?
1. CH4
2. C2H4
3. C3H8
4. C4H10
Answer:
The second one
Explanation:
Because not only did I take a castle learning in this today but c2h4 has 6 covalent bonds
There are several types of molecules that have multiple bond. A molecule of which compound has a multiple covalent bond is C2H4.
Covalent bonding is the sharing of one or more electron pairs. In many covalent bonding situations,
Multiple chemical bonds exist when there is more than one electron pair that is being shared.
A nitrogen atom often fill its octet by sharing three electrons with another nitrogen atom thereby creating three covalent bonds.
Multiple bonds are commonly found in organic compound and they have carbon molecules.
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Which factor would slow down a chemical reaction? (Choose all that apply)
A)Adding an inhibitor
B)Decreasing temperature
C)Decreasing particle size
D)Increasing particle size
Answer:
(decreasing particle size) C
Explanation: That is one of the answers, if there are more I am sorry.
When a gas particle changes phase into a liquid particle:
A. the particle loses energy
B. the particle gains energy
C. the particle has no change in energy
D. the change in energy depends on the type of gas
Answer:B
Explanation:
The movement in particles is faster than the particle movement in a solid and the attractive forces are much weaker.A gas is something with no definite volume and no definite shape. Gas particles are far apart and move rapidly and freely. The attractive forces between gas particles are very weak or absent.When a liquid is heated, the particles are given more energy. They start to move faster and further apart. At a certain temperature, the particles break free of one another and the liquid turns to gas. This is the boiling point.Particles in gas are well separated with no regular arrangement. liquid are close together with no regular arrangement. Solid are tightly packed, usually in a regular pattern.the diagram above represents a reflex arc in a human. This pathway responds when someone touches something that causes pain, such as a hot stove. Which of the following shows the correct order of the body systems involved in this response?
A) Integumentary, respiratory, digestive
B) Circulatory, respiratory, nervous
C) Integumentary, nervous, muscular
D) Circulatory, digestive, nervous
Answer:
C) Integumentary, nervous, muscular
Explanation:
When a human body touches a hot stove , our sense organ which is integumen first of all receives the impulse of heat . The impulse is transformed into electrical signal which is transmitted to brain which is a part of nervous system . Then brain processes it and command signal is sent to muscle of hand to move it away from that place . Hence the order is
Integumentary, nervous, muscular .
6. Bacteriorhodopsin is an integral membrane protein that uses solar energy (absorbed by its retinal chromophore) to pump protons out of the cell against an electrochemical gradient. Re-entry of the protons into the cell (down the gradient through its ATPase) is then used to drive the synthesis of ATP from ADP and Pi. Consider the following conditions: intracellular pH is 9.4 and extracellular pH is 6.4, and there is a transmembrane electrical gradient of 120 mV (negative inside). The concentration of intracellular [ATP] = 1 mM, [ADP] = 50 µM, and [Pi] = 2 mM, and G° for ATP hydrolysis is -30.5 kJ/mol. Temperature is 27 °C. a. What is the energy cost of pumping one mole of H+ out of the cell? b. What is the minimal number of H+ that must re-enter the cell through the ATPase to provide sufficient energy to synthesize each ATP? Explain how you arrived at this answer quantitatively, of course.
Answer:
Explanation:
Hello!
a)
You have an integral membrane protein (Bacteriorhodopsin) that uses solar energy to pump protons out of the cell against its electrochemical gradient.
To calculate the energy needed by the protein to pump one molecule out of the cell you need to apply the free energy difference equation for a charged molecule:
ΔG= 2.303RTlog₁₀[tex](\frac{[H^+]out}{[H^+]in})[/tex]+zFΔV
Where
ΔG= free energy difference per molecule transferred from the inside to the outside
R= gas constant 8.315*10⁻³ kJ/mol
T= Temperature in Kelvin (273.15 + TºC)
z= Valency of the ion (ej Na⁺ is z= +1 and Cl⁻ is z= -1)
F= Faraday constant 96.5 kJ/V*mol
ΔV= membrane potential (Volts)
The information you have is:
Intracellular pH= 9.4
Extracellular pH= 6.4
ΔV= 120 mV
Temperature 27ºC
Using the values of pH you can calculate the intracellular and extracellular proton concentrations:
Remember the pH of a solution is calculated as pH=-log[H⁺] so if you reverse the logarithm, you'll find the concentration of protons:
b= logₐ C ⇒ C= aᵇ
[H⁺]intracelular= 10⁻⁹'⁴
[H⁺]extracelular= 10⁻⁶'⁴
Now you need to match the units of the temperature and electrical gradient to the ones in the equation:
The temperature needs to ve in Kelvin: T= 273.15 + 27ºC= 300.15K
The electrical gradients need to be in Volts: ΔV= 120 mV= 0.12V
Now you can replace the data in the formula and calculate how much energy is needed to pump one proton outside the cell:
ΔG= 2.303RTlog₁₀[tex](\frac{[H^+]out}{[H^+]in})[/tex]+zFΔV= 2.303*( 8.315*10⁻³ kJ/mol)*300.15K*log[tex](\frac{10^{-6.4}}{ 10^{-9.4}} )[/tex]+(+1)*96.5 kJ/V*mol*0.12V= 28.82 kJ/mol
It costs 28.82 kJ/mol to pump one mole of H⁺ outside the cell.
b)
To synthesize one molecule of ATP the ATP synthase uses the electrical gradient produced by the spontaneous pass of protons through the membrane. This process is called the proton-motive force.
The ATP synthase consists of two subunits F₀ and F₁ with a rotational motor mechanism that allows it to produce and release ATP.
F₁ has the subunits α, β, σ, γ, ε in charge of synthesizing ATP
F₀ is a proton pore, made of 3 subunits a, b and c. 6 subunits c make up the transmembrane ring in charge of rotation, this ring is connected to the subunits γ and ε. Each time a proton passes, it makes the ring rotate which makes the subunits γ rotate.
Each time the subunit γ rotates 360º, 3 ATP molecules are synthesized and freed. A full rotation of γ means that the c-ring also made a full rotation (for this you need one proton per subunit)
If the ring has 6 c-subunits and, then each ATP molecule needs 6/3= 2 protons to need to pass for each ATP molecule.
I hope this helps!
What type of ions do metals produce?
Answer:
Ionic bonds
Explanation:
It rymes. haha i dont even know how to spell it! ;)
