Answer:
D
Explanation:
8oz=1cup
Xoz=1/4cup
cross multiply
Xoz=8×1/4=2
2oz=1/4cup
1oz=2T
2oz=x
cross multiply
×=2×2=4T
The cup of butter, number of tablespoons and ounces of butter are all in direct proportion with one another. The interpretation of the information provided is:
(b). The information provided gives the conversion factor 8oz/1 cup.
Given that:
[tex]1\ recipe = \frac{1}{4}\ cup[/tex]
[tex]1\ oz = 2T[/tex]
[tex]8\ oz = 1\ cup[/tex]
Multiply both sides of [tex]1\ oz = 2T[/tex] by 8
[tex]8 \times 1oz = 8 \times 2T[/tex]
[tex]8 oz = 16T[/tex]
Substitute 8oz for 1 cup in: [tex]1\ recipe = \frac{1}{4}\ cup[/tex]
[tex]1\ recipe = \frac{1}{4} \times 8oz[/tex]
Substitute [tex]8 oz = 16T[/tex]
[tex]1\ recipe = \frac{1}{4} \times 16T[/tex]
[tex]1\ recipe = 4T[/tex]
The interpretations are as follows:
[tex]1\ recipe = 4T[/tex] means that 1 recipe requires 4T of butter [tex]8\ oz = 1\ cup[/tex] means that the information provided gives a conversion of 8oz/1 cupHence, (b) is correct
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At a given temperature, K = 1.3x10^-2 for the reaction:
N2(g) + 3H2(g) ⇌ 2NH3(g)
Calculate values of K for the following reactions at this temperature.
a. 1/2N2 + 3/2H2(g) ⇌ NH3(g)
b. 2NH3(g) ⇌ N2(g) + 3H2(g)
c. NH3(g) ⇌ 1/2 N2(g) + 3/2H2(g)
d. 2N2(g) + 6H2(g) ⇌ 4NH3(g)
Answer:
a) 0.11
b)76.9
c) 8.8
d) 1.7*10^-4
Explanation:
Step 1: Data given
K = 1.3 * 10^-2 for the reaction N2(g) + 3H2(g) ⇌ 2NH3(g)
Step 2: Formula of K
aA(g) + bB(g) ⇌ cC(g) + dD(g)
K = [C]^c *[D]^d / [A]^a * [B]^b
K = 1.3 * 10^-2 = [NH3]² / [H2]³*[N2]
Step 3:
a) 1/2N2 + 3/2H2(g) ⇌ NH3(g)
N2(g) + 3H2(g) ⇌ 2NH3
1/2N2 + 3/2H2(g) ⇌ NH3(g) =>K' = [tex]\sqrt{K}[/tex]
K' = [tex]\sqrt{1.3*10^-2}[/tex] = 0.11
b. 2NH3(g) ⇌ N2(g) + 3H2(g)
N2(g) + 3H2(g) ⇌ 2NH3
2NH3(g) ⇌ N2(g) + 3H2(g) =>K' = 1/K
K' = 1/(1.3*10^-2) = 76.9
c. NH3(g) ⇌ 1/2 N2(g) + 3/2H2(g)
N2(g) + 3H2(g) ⇌ 2NH3
NH3(g) ⇌ 1/2 N2(g) + 3/2H2(g)
=>K' = [tex]\frac{1}{\sqrt{K} }[/tex]
K' = [tex]\frac{1}{\sqrt{1.3*10^-2} }[/tex]
K' = 8.8
d. 2N2(g) + 6H2(g) ⇌ 4NH3(g)
N2(g) + 3H2(g) ⇌ 2NH3
2N2(g) + 6H2(g) ⇌ 4NH3(g)
K' = K²
K' = (1.3*10^-2)²
K' = 1.7 *10 ^-4
Values of equilibrium constant at given temperature for the following reactions are 0.11, 76.9, 8.8 and 1.7 × 10⁻⁴ respectively.
How we calculate equilibrium constant?Equilibrium constant is define as the ration of the concentrations of product to the concentrations of reactant with respect to the exponent of their coefficients.
Given chemical reaction is:
N₂(g) + 3H₂(g) ⇌ 2NH₃(g)
Equilibrium constant for this reaction is:
K = [NH₃]² / [N₂][H₂]³
K = 1.3 × 10⁻² (given)
Equilibrium constant K₁ for below reaction will be written as:1/2N₂(g) + 3/2H₂(g) ⇌ NH₃(g)
K₁ = √K
Because concentration of all given species is 1/2 of the given reaction, so value of K₁ will be written as:
K₁ = √(1.3 × 10⁻²) = 0.11
2NH₃(g) ⇌ N₂(g) + 3H₂(g)
K₂ = 1/K
Because concentration of reactant and products are reciprocal from the concentration of original given reaction, so value of K₂ will be written as:
K₂ = 1/1.3 × 10⁻² = 76.9
NH₃(g) ⇌ 1/2N₂(g) + 3/2H₂(g)
K₃ = 1/√K
Because concentrations of given species is reciprocal as well as half of the given original reaction, so value of K₃ will be written as:
K₃ = 1/√(1.3 × 10⁻²) = 8.8
2N₂(g) + 6H₂(g) ⇌ 4NH₃(g)
K₄ = K²
Because concentrations of given species is double of the given original reaction, so value of K₄ will be written as:
K₄ = (1.3 × 10⁻²)² = 1.7 × 10⁻⁴
Hence, the value of K for given reactions are 0.11, 76.9, 8.8 and 1.7 × 10⁻⁴ respectively.
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Question 6
Based on your observations, what conclusion can you draw about the lengths of AD, DB, AE, and EC?
Answer: The ratio of AD to DB is equal to the ratio of AE to EC. In other words, the pairs of lengths are proportional.
Explanation:
Sample answer from plato
Answer:
The pairs of lengths are proportional, because, the ratios of AD and DB are the exact same, so they are equal to the ratios of the set AE and EC.
Explanation:
It is rewritten from a sample answer from Plato just to be safe from plagiarism.
does light appears to travel in straight lines. travelling from light sources until it hits the surface of an object?? (Truer or False) if your answer is true then what is the reason why does light appears to travel in straight lines??.
Answer:
true once light has been produce it will keep travelling jn straight parts until it hits something else
Chair and Boat Conformers of Cyclohexane (C6H12). Note it is impossible to place all the carbons in the same plane without straining the bonds. Take two opposite carbons and pull both of them up to make one conformation and then pull one of them down to make the other conformation.
a. Can you interconvert one conformer into the other without breaking any bonds?
b. Explain why these represent conformers and not isomers.
Answer:
See explanation
Explanation:
Conformation refers to the various spatial arrangements of atoms in a molecule that result from free rotation across the carbon-carbon single bond.
There are two possible conformations of cyclohexane. They are; the chair and boat conformations.
We can convert the molecule from one conformation to another by rotation of single bonds.
These conformations are not isomers. Isomers are different molecules while conformers are different spatial arrangements of the same molecule obtained by rotation across carbon-carbon single bonds. Isomers are not obtained by rotation across carbon-carbon single bonds.
Hence, the chair and boat conformers of cyclohexane are obtained by rotation across the carbon-carbon single bond hence they are conformers and not isomers.
A hot ballon with mass of 400 kilograms moves across the aky with 3,200 joules of kinetic energy. The velocity of the ballon is
Answer:
4 m/s
Explanation:
formula is v = (KE/.5m)^1/2
there is a calculator
https://www.calculatorsoup.com/calculators/physics/kinetic.php
Amphipathic molecules are ________; not able to interact via van der Waals forces. A) Polar only B) Nonpolar only C) Neither polar nor nonpolar D) Both polar and nonpolar
Answer:
D) Both polar and nonpolar.
Explanation:
Hello there!
In this case, according to the given statement, it turns out possible for us to bear to mind the fact the amphiphatic molecules are composed by two parts, the hydrophilic and the hydrophobic, being the former polar and the latter nonpolar as the example shown on the attached figure.
In such a way, we infer that the correct answer is D) Both polar and nonpolar.
Regards!
Why is there a huge diversity of substances?
A. Atoms can combine in many ways to form various compounds
and molecules.
B. Any element can combine with any other element.
C. Atoms break apart to form new types of atoms during chemical
reactions.
D. There is an unlimited number of elements.
A. Atoms can combine in many ways to form various compounds
and molecules.
Diazomethane has the molecular formula CH2N2. Draw the preferred Lewis structure for diazomethane and assign formal charges to all atoms, if any.
Answer:
See explanation
Explanation:
We define the formal charge on an atom in a molecule as the charge it carries assuming that electrons in all chemical bonds of the molecule were shared equally between atoms irrespective of the electronegativity of each atom.
The formula for calculating the formal charge on an atom in a molecule is;
Formal Charge = [number of valence electrons on neutral atom] – [(number of lone electron pairs) + (½ number of bonding electrons)] ·
The formal charge on the two nitrogen atoms in diazomethane is obtained as follows;
Middle nitrogen atom = 5 – 8/2 – 0 = +1
Last nitrogen atom = 5 – 4/2 – 4 = –1
The Lewis structure of the molecule is shown in the image attached.
The pH of a solution with a hydrogen-ion concentration of 4.90 x 10-'Mi
Please answe I’ll give you brainliest
Answer:
pH < 7; pH = 7; pH > 7
Explanation:
when dealing with an acidic base, you have the formula for [H3O+] > [OH-] which yields a pH < 7.
when you have a neutral base, the reactive ion concentration would be [H3O^+] = [OH^-] which yields a pH = 7.
finally, when dealing with a basic classification, the formula would be [H3O^+] < [OH^-] yields a pH > 7.
You pre-weigh a glass vial to hold your sample and find its mass to be 5.010 g. You add your sample to the vial and reweigh it on the same balance and find that the mass has increased to 6.130 g. What is the mass of the sample in grams
When we pre-weigh a glass vial to hold our sample and find its mass to be 5.010 g. Then we add our sample to the vial and reweigh it on the same balance and find that the mass has increased to 6.130 g. The mass of the sample in grams is 1.12 g.
What is mole concept?Avogadro's number is the number of units in one mole of any substance and equals to 6.02214076 × 10²³. The units can be electrons, atoms, ions, or molecules.
No. of moles is defined as a particular no. of particles that we can calculate with the help of Avogadro’s number.
Mass of a particular product is also find out by stoichiometry of a reaction as per the no. of mole given in the reaction.
Mass is generally can be represented by units like Kg, g etc.
Given,
weigh of glass vial = 5.010 g
weigh of glass vial with sample = 6.130 g
Therefore, When we pre-weigh a glass vial to hold our sample and find its mass to be 5.010 g. Then we add our sample to the vial and reweigh it on the same balance and find that the mass has increased to 6.130 g. The mass of the sample in grams is 1.12 g.
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Which reaction produces an insoluble product?
A
2KI + Pb(NO )2 → → PbI, + 2KNO
B
2AgNO3 + Ca(CH,02)2 + Ca(NO3)2 + 2AgC,H,O,
C
3BaCl2 + ALLS
→ 2AlCl3 + 3BaS
.
D
SrBr, + Mg(OH)2 → MgBr, + Sr(OH)2
Answer: The correct option is A).
Explanation:
Precipitation reaction is defined as the reaction where a solid precipitate (solid substance) is formed at the end of the reaction. It is insoluble in water.
For the given chemical reactions:
A): [tex]2KI+Pb(NO_3)_2\rightarrow PbI_2+2KNO_3[/tex]
The iodide of lead is generally insoluble in water. Thus, lead iodide is a precipitate.
B): [tex]2AgNO_3+Ca(CH_3COO)_2\rightarrow Ca(NO_3)_2+2CH_3COOAg[/tex]
The nitrates and acetates of all metals are soluble in water.
C): [tex]3BaCl_2+Al_2S_3\rightarrow 2AlCl_3+3BaS[/tex]
The sulfide of barium is soluble in water.
D): [tex]SrBr_2+Mg(OH)_2\rightarrow MgBr_2+Sr(OH)_2[/tex]
The hydroxide of strontium is soluble in water.
Hence, the correct option is A).
why ionic compound are good conduct of electricity in their molten state ??
Answer:
Ionic compounds conduct electricity when molten (liquid) or in aqueous solution (dissolved in water), because their ions are free to move from place to place. Ionic compounds cannot conduct electricity when solid, as their ions are held in fixed positions and cannot move.
Explanation:
because their ions are free to move from place to place.
Consider the following reaction at 298 K.
2 SO2(g) + O2(g) → 2 SO3(g)
An equilibrium mixture contains O2(g) and SO3(g) at partial pressures of 0.43 atm and 2.6 atm, respectively. Using data from Appendix 4, determine the equilibrium partial pressure of SO2 in the mixture.
______atm.
Answer and Explanation:
The reaction is in the gas phase, so the equilibrium constant is expressed in terms of the partial pressures (P) of the products and reactants, as follows:
[tex]Kp = \frac{P^{2}_{SO_{3} } }{P_{SO_{2}} ^{2}P_{O_{2}} }[/tex]
We have the following data:
P(SO₃) = 2.6 atm
P(O₂) = 0.43 atm
We need Kp for this reaction. We can assume that in Appendix 4 we found that Kp = 7 x 10²⁴.
Then, we introduce the data in the equilibrium constant expression to calculate the partial pressure f SO₂ (PSO₂), as follows:
[tex]P_{SO_{2} } = \sqrt{\frac{P_{SO_{3} } ^{2} }{Kp P_{O_{2} } } } = \sqrt{\frac{(2.6 atm)^{2} }{(7 x 10^{24)}(0.43 atm) } } = 1.5 x 10^{-12} atm[/tex]
Therefore, the partial pressure of SO₂ is 1.5 x 10⁻¹² atm (for the given Kp).
Consider these two cases.
Case 1: An electron jumps from energy level 1 to energy level 2 in an atom.
Case 2: An electron jumps from energy level 1 to energy level 3 in an atom.
For case 1, what happens when an electron jumps from energy level 1 to energy level 3 in an atom?
A. A photon is absorbed by the atom.
B. A photon is emitted by the atom.
C. A proton is absorbed by the atom.
D. A proton is emitted by the atom.
Assuming that both cases describe Hydrogen-like atoms with one electron, for which case is more energy emitted or absorbed?
A. The energy is the same for both cases.
B. More energy is emitted or absorbed for case 2
C. It is impossible to tell.
D. More energy is emitted or absorbed for case 1
Answer:
A photon is absorbed by the atom.
More energy is emitted or absorbed for case 2
Explanation:
According to the Bohr model of the atom, electrons occur in energy levels. The energy of each level is fixed. However, electrons can absorb photons and move from a lower to higher energy level or emit photons and move from a higher to a lower energy level.
In each case, the energy absorbed or emitted is equal to the difference in energy between the two energy levels.
Since energy level 3 is much higher than energy level 2, the electron absorbs more energy in moving from energy level 1 to energy level 3 than it absorbs when moving from energy level 1 to energy level 2.
Fossils of a dinosaurs would most likely be found in
A)
conglomerate rock
B) sedimentary rock
C)
Igneous rock
D)
metamorphic rock
Answer:
b
Explanation:
Answer:
B
Explanation:
An organelle that is not found in this illustration of a cell would be
A. the cell wall
B. chromosome
C. mitochondria
D. the cell membrane
Answer:
The answer is cell wall
Explanation:
Because it is
OT protons (d) (a) and (b)
3. Atoms of active elements have
(a) complete outermost orbit
(c) inert gas configuration
(b) incomplete outermost orbit
(d) complete dupletm
Answer:
A.
Explanation:
sana makatulong sayo
g) The set of quantum numbers for the 6th electron in fluorine atom.
Answer:
n=2, l= 1, m= 0, s = +1/2
Explanation:
An electron is described by four sets of quantum numbers;
I) principal quantum number (n)
ii) orbital quantum number (l)
iii)Magnetic quantum number (m)
iv) Spin quantum number (s)
The electronic configuration of fluorine is; 1s2 2s2 2p5
Hence, the sixth electron of fluorine is found in the 2p subshell where;
n=2, l= 1, m= 0, s = +1/2
Aqueous hydrochloric acid reacts with solid sodium hydroxide to produce aqueous sodium chloride and liquid water . What is the theoretical yield of sodium chloride formed from the reaction of 0.73g of hydrochloric acid and 1.3g of sodium hydroxide?
Round your answer to 2 significant figures.
i think its 2.0
Why do i think this-If you add 0.73g to 1.3g it comes to 2.0g
Calculate the mass of CaCL2 formed when 5 moles of chlorine reacts with calcium metal....
Answer:
555 g of CaCl₂
Explanation:
We'll begin by writing the balanced equation for the reaction. This is given below:
Ca + Cl₂ —> CaCl₂
From the balanced equation above,
1 mole of Cl₂ reacted to produce 1 mole of CaCl₂.
Next, we shall determine the number of mole of CaCl₂ produced by the reaction of 5 moles of Cl₂. This can be obtained as follow:
From the balanced equation above,
1 mole of Cl₂ reacted to produce 1 mole CaCl₂.
Therefore, 5 moles of Cl₂ will also react to produce 5 moles of CaCl₂.
Thus, 5 moles of CaCl₂ were obtained from the reaction.
Finally, we shall determine the mass of 5 moles of CaCl₂. This can be obtained as follow:
Mole of CaCl₂ = 5 moles
Molar mass of CaCl₂ = 40 + (35.5×2)
= 40 + 71
= 111 g/mol
Mass of CaCl₂ =?
Mass = mole × molar mass
Mass of CaCl₂ = 5 × 111
Mass of CaCl₂ = 555 g
Therefore, 555 g of CaCl₂ were obtained from the reaction.
What is black body radiation?
Explanation:
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Do your structures resemble the following?
H-C=C-H
Answer:
For the HCCH Lewis structure you'll need to form a triple bond between the two carbon atoms. Hydrogen atoms only need two electrons for a full outer shell. There are a total of 10 valence electrons for the HCCH Lewis structure.
One mole of
C
2
H
6
O
C
2
H
6
O has two moles of Carbon (C), six moles of Hydrogen (H) and one mole of Oxygen (O). How many moles of Hydrogen is in 0.2 moles of
C
2
H
6
O
C
2
H
6
O?
Answer:
c
no need to thank me okay
The equilibrium constant, Kc, for the following reaction is 77.5 at 600 K. CO(g) Cl2(g) COCl2(g) Calculate the equilibrium concentrations of reactant and products when 0.555 moles of CO and 0.555 moles of Cl2 are introduced into a 1.00 L vessel at 600 K.
Answer:
[CO] = 0.078M
[Cl2] = 0.078M
[COCl2] = 0.477M
Explanation:
Based on the reaction:
CO(g) Cl2(g) ⇄ COCl2(g)
Where equilibrium constant, kc, is:
kc = 77.5 = [COCl2] / [CO] [Cl2]
[] represents the equilibrium concentration of each gas. The initial concentration of each gas is:
[CO] = 0.555mol/1.00L = 0.555M
[Cl2] = 0.555M
And equilibrium concentrations are:
[CO] = 0.555M - x
[Cl2] = 0.555M - x
[COCl2] = x
Where x is reaction coordinate
Replacing in kc expression:
77.5 = [x] / [0.555M - x] [0.555M - x]
77.5 = x / 0.308025 - 1.11 x + x²
23.8719 - 86.025 x + 77.5 x² = x
23.8719 - 87.025 x + 77.5 x² = 0
x = 0.477M. Right answer
x = 0.646M. False answer. Produce negative concentrations
Replacing:
[CO] = 0.555M - 0.477M = 0.078M[Cl2] = 0.078M[COCl2] = 0.477MAnd those concentrations are the equilibrium concentrations
For each amino acid, the name, three-letter abbreviation, or one-letter abbreviation is given. Complete the missing information name: proline three-letter abbreviation: one-letter abbreviation: Select the class (side chain) for proline. name: three-letter abbreviation: Phe name: three-letter abbreviation: Phe one-letter abbreviation: Select the class (side chain) for Phe. name: three-letter abbreviation: name: three-letter abbreviation: one-letter abbreviation: D Select the class (side chain) for D. nathe: lysine three-letter abbreviation: latihan aidantului one-letter abbreviation: Select the class (side chain) for lysine. name: three-letter abbreviation: Gin one-letter abbreviation: Select the class (side chain) for Gln.
A new student is planning to use thin layer chromatography (TLC) for his research project. After setting up the apparatus the student forgets to place a lid on the TLC jar. He obtains poor results after running the TLC experiment. Which of the following can best explain his bad results?
A. The open system evaporates the solvent on the TLC plate
B. The open system prevents the evaporation of the solvent in the solution
C. The open system prevents the evaporation of the solvent on the TLC plate
D. The open system evaporates the solvent in the solution
Answer:
The open system evaporates the solvent in the solution
Explanation:
An open system is a system in which exchange of materials and energy can occur. If a TLC set up is left open, then the set up constitutes an open system.
During TLC, the sample is dotted on the plate and inserted into a suitable solvent. The solvent moves up the plate and achieves the required separation of the mixture.
Most of these solvents used used TLC are volatile organic compounds. Therefore, if the TLC set up is left open, the solvent will evaporate leading to poor results after running the TLC experiment.
A 11.79 g sample of Mo2O3(s) is converted completely to another molybdenum oxide by adding oxygen. The new oxide has a mass of 14.151 g . Add subscripts to correctly identify the empirical formula of the new oxide.
Answer:
MoO₃
Explanation:
To solve this question we must find the moles of molybdenum in Mo2O3. The moles of Mo remain constant in the new oxide. With the differences in masses we can find the mass of oxygen and its moles obtaining the empirical formula as follows:
Moles Mo2O3 -Molar mass: 239,878g/mol-
11.79g * (1mol / 239.878g) = 0.04915 moles Mo2O3 * (2mol Mo / 1mol Mo2O3) = 0.09830 moles Mo
Mass Mo in the oxides:
0.09830 moles Mo * (95.95g/mol) = 9.432g Mo
Mass oxygen in the new oxide:
14.151g - 9.432g = 4.719g oxygen
Moles Oxygen:
4.719g oxygen * (1mol/16g) = 0.2949 moles O
The ratio of moles of O/Mo:
0.2949molO / 0.09830mol Mo = 3
That means there are 3 moles of oxygen per mole of Molybdenum and the empirical formula is:
MoO₃a weak acid undergoes _ ionization in water
Answer:
Partial
Explanation:
A strong acid will completely ionize in water while a weak acid will only partially ionize.
Phosphorus pentachloride, PCl5, a white solid that has a pungent, unpleasant odor, is used as a catalyst for certain organic reactions. Calculate the number of moles in 38.7 g of PCl5.
Answer:
0.186 moles
Explanation:
In order to convert grams of PCl₅ into moles, we need to use its molar mass:
Molar Mass of PCl₅ = Molar mass of P + (Molar mass of Cl)*5Molar Mass of PCl₅ = 208.24 g/molThen we proceed to calculate the number of moles:
38.7 g ÷ 208.24 g/mol = 0.186 molThere are 0.186 moles of PCl₅ in 38.7 g of PCl₅.In the given question Phosphorus pentachloride is used as a catalyst for certain chemical reaction. 38.7 g of [tex]\rm PCl_5[/tex], there are 0.186 moles of [tex]\rm PCl_5[/tex].
A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy required for the reaction to occur.
To calculate the number of moles in 38.7 g of [tex]\rm PCl_5[/tex], we need to divide the given mass of [tex]\rm PCl_5[/tex] by its molar mass.
The molar mass of [tex]\rm PCl_5[/tex] can be calculated by adding the atomic masses of one phosphorus atom and five chlorine atoms:
Molar mass of [tex]\rm PCl_5[/tex] = (1 x atomic mass of P) + (5 x atomic mass of Cl)
= (1 x 30.97 g/mol) + (5 x 35.45 g/mol)
= 208.22 g/mol
Now, we can calculate the number of moles of [tex]\rm PCl_5[/tex]:
Number of moles = mass / molar mass
= 38.7 g / 208.22 g/mol
= 0.186 moles
Therefore, there are 0.186 moles of [tex]\rm PCl_5[/tex] in 38.7 g of [tex]\rm PCl_5[/tex].
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17. Which of the following is a device that generates electricity using a chemical reaction?
O A. Fuel cell
B. Battery
C. Charging station
O D. Solar panel
Answer:
Hydrogen and fuel cell technologies power cars, buildings and more. But how ... Test your knowledge with this quiz! ... How do fuel cells generate electricity
Answer:
A
Explanation:
fuel cell is a device that converts the chemical energy from fuel into electricity via a chemical reaction with oxygen or another oxidizing agent. Batteries work in a closed system, while fuel cells require their reactants to be replenished.