The student heated a 2.00 g sample of a hydrate of CoCl2 and obtained 1.09 g of the anhydrate after cooling. The mass of water released can be calculated by subtracting the mass of the anhydrate from the initial mass of the hydrate: 2.00 g - 1.09 g = 0.91 g. Therefore, the mass of water released is 0.91 g.
To determine the percent of water of hydration, we need to compare the mass of water released to the mass of the original hydrate. The percent of water of hydration can be calculated using the formula: (mass of water released / mass of hydrate) x 100%. In this case, the mass of the original hydrate is 2.00 g. Plugging in the values, we get (0.91 g / 2.00 g) x 100% = 45.5%. Therefore, the percent of water of hydration is 45.5%.
To find the formula of the hydrate, we need to determine the ratio between the moles of water and the moles of anhydrate. We can use the molar masses of water (18.015 g/mol) and CoCl_{2} (129.841 g/mol) to calculate the moles of each component. The moles of water can be found by dividing the mass of water released by its molar mass: 0.91 g / 18.015 g/mol = 0.0505 mol. The moles of anhydrate can be calculated similarly: 1.09 g / 129.841 g/mol = 0.0084 mol. To find the ratio, we divide the moles of water by the moles of anhydrate: 0.0505 mol / 0.0084 mol ≈ 6.01. This means that the formula of the hydrate is[tex]CoCl_{2}[/tex]·[tex]6H_{2}O[/tex], indicating that for every[tex]CoCl_{2}[/tex] unit, there are six water molecules associated with it.
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The mass of water released is 0.91 g. The percent of water of hydration is 45.5%. The formula of the hydrate is likely CoCl2 · H2O.
Explanation:To determine the mass of water released, we subtract the mass of the anhydrate from the mass of the initial hydrate: 2.00 g - 1.09 g = 0.91 g. The percent of water of hydration can be calculated by dividing the mass of water released by the mass of the initial hydrate and multiplying by 100: (0.91 g / 2.00 g) * 100 = 45.5%. From the information given, we can find the formula of the hydrate by comparing the molar masses of the anhydrate and the water: (1.09 g / 0.91 g) = 1.20. Since this is close to a 1:1 ratio, the formula of the hydrate is likely CoCl2 · H2O.
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Characteristics that are used to help identify an object are called
acid-catalyzed addition of alcohols to alkenes proceeds in a mechanism analogous to the acid-catalyzed addition of water to yield ethers. true or false
We can see here that the acid-catalyzed addition of alcohols to alkenes proceeds in a mechanism analogous to the acid-catalyzed addition of water to yield ethers. True.
What is alcohol?Alcohol is a broad term that refers to a class of organic compounds characterized by the presence of a hydroxyl (-OH) functional group attached to a carbon atom.
The acid-catalyzed addition of alcohols to alkenes is a useful reaction for the synthesis of ethers. It is also a relatively mild reaction, which makes it a good choice for the synthesis of ethers from sensitive compounds.
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if you wish to observe features that are around the size of atoms, say 6.5 × 10-10 m, with electromagnetic radiation, the radiation must have a wavelength of about the size of the atom itself. (a) What is its frequency? (b) What type of electromagnetic radiation might this be?
(a) The frequency of electromagnetic radiation required to observe features around the size of atoms is approximately 4.6 × 10⁻¹⁹ Hz, (b) This type of electromagnetic radiation might be X-rays.
The relationship between the wavelength is (λ), frequency is (ν), and the speed of light is (c) is given by the equation c = λν. The atom size and the size of the wavelength should be same. Therefore, λ ≈ 6.5 × 10⁻¹⁰ m. Now, rearranging and solving,
ν = c/λ
ν = (3×10⁸m/s)/(6.5×10⁻¹⁰m)
ν ≈ 4.6 × 10¹⁹ Hz
Hence, the frequency of electromagnetic radiation required to observe features around the size of atoms is approximately 4.6 × 10¹⁹ Hz. This is X-rays.
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Which wavelength corresponds to photons with a greater energy?
a. 320 nm
b. 530 nm
c. they are equal in energy
The wavelength that corresponds to photons with greater energy is 320 nm. Hence, option a is correct.
The energy of a photon is inversely proportional to its wavelength according to the equation:
E = hc/λ
where E is the energy of the photon, h is Planck's constant (approximately 6.626 x 10^-34 J·s), c is the speed of light (approximately 3.00 x 10^8 m/s), and λ is the wavelength of the photon.
Since energy (E) is inversely proportional to wavelength (λ), shorter wavelengths correspond to photons with greater energy. Therefore, the photon with a wavelength of 320 nm has greater energy compared to the photon with a wavelength of 530 nm.
The wavelength that corresponds to photons with greater energy is 320 nm (option a).
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2. The density of helium is 1.78 X 104 g/cm. What is this
density in Dg/um??
Answer:
[tex]d=1.78\times 10^{-7}\ Dg/\mu m^3[/tex]
Explanation:
Given,
The density of Helium is [tex]1.78\times 10^4\ g/cm^3[/tex]
We need to find the density in Dg/μm
We know that,
1 g = 10 dg
1 cm³ = 10¹² μm³
So,
[tex]d=1.78 \times 10^4\ g/cm^3\\\\=1.78 \times 10^4\times \dfrac{10\ dg}{10^{12}\ \mu m^3}\\\\=1.78\times 10^{-7}\ Dg/\mu m^3[/tex]
So, the density of Helium is equal to [tex]1.78\times 10^{-7}\ Dg/\mu m^3[/tex].
this is due in five mintues please help
Answer:
5
Explanation:
Na, N, O, O, O
Homeostasis refers to
A.
the similarity of genetic traits to one another.
B.
a mixture or solution that is the same throughout.
C.
the tendency of a cell to maintain a stable internal environment.
D.
the effect of natural selection on human evolution.
NEED HELP QUICK!!!!!!!!
Answer:
(C)
the tendency of a cell to maintain a stable internal environment.
Answer:
Homeostasis refers to C. the tendency of a cell to maintain a stable internal environment.
Which of the following statement is not true?
Answer: 2
Explanation: Greenhouse gases are very important in keeping our planet just right. If we have too many Greenhouse gases it would be too hot, but we can't eliminate all of them or it will be too cold
If HCl is a weaker acid than HI, why is ClCH2COOH a stronger acid than ICH2COOH?
a.)Because Cl is more electronegative than I.
b.)Because ICH2COO− is more stable than ClCH2COO−
c.)Because the size of Cl atom is greater than the size of I atom.
d.)Because I− is more stable than Cl−
The correct option is A. Because Cl is more b electronegative than I.
Both ICH2COOH and ClCH2COOH are members of the carboxylic acid family. The acidity of carboxylic acids is generated by their carboxyl group (-COOH). When it comes to acidity, there are numerous factors to consider. The acidity of a carboxylic acid is determined by its carboxyl group and the substituents on the carbon atom adjacent to the carboxyl group. In the case of carboxylic acids, the strength of the acid increases as the substituents on the carbon atom adjacent to the carboxyl group become increasingly electron-withdrawing or electronegative.
A carboxylic acid with a strong electron-withdrawing substituent on the adjacent carbon atom is more acidic than a carboxylic acid with a weak electron-withdrawing substituent on the adjacent carbon atom. When we look at the two molecules, ICH2COOH and ClCH2COOH, we see that they have the same chemical structure except for the halogen substituent. The electronegativity of Cl is more than that of I, which means that Cl is more electron-withdrawing than I. As a result, ClCH2COOH has a stronger electron-withdrawing group attached to it, making it a stronger acid than ICH2COOH. Therefore, the correct option is A. Because Cl is more electronegative than I.
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. can steam distillation of ethanol be done? why or why not?
Yes, steam distillation of ethanol can be done. Steam distillation is a technique used to separate volatile compounds from non-volatile or less volatile substances. Ethanol is a volatile compound with a boiling point of approximately 78.4 °C.
In steam distillation, the mixture containing the volatile compound (in this case, ethanol) is heated, and steam is passed through the mixture. The steam carries the volatile compound along with it, and the mixture is then condensed to separate the volatile compound from the non-volatile components.
Ethanol forms an azeotropic mixture with water, meaning that the boiling point of the mixture is lower than the boiling points of the individual components. In the case of ethanol-water mixture, the boiling point of the azeotropic mixture is around 78.2 °C, slightly lower than pure ethanol. This azeotropic behavior actually facilitates the steam distillation process of ethanol because the steam carries along the ethanol vapor more effectively.
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Are these ramen noodles expired?
Answer:
i think so
Explanation:
just eat them anyways
Answer: Yes they are
Explanation: Where's the picture?
help cococococo cococococo doing this for the points or whatever it is cococo
Answer:
what is cocococococo?
Explanation:
isnt it like a plant for choclate?
Answer:
hhhhhhhh
Explanation:
How is activation energy represented on an energy diagram?
Energy
Reactants
Products
Reaction Progress
O A. Activation energy is the distance from the reactants to the top of
the "hill."
B. Activation energy is the distance from the top of the "hill to the
products.
O C. Activation energy is the final energy level of the product
molecules.
o
D. Activation energy is the starting energy level of the reactant
molecules.
In accordance with the diagram, activation energy is the distance from the reactants to the top of the "hill"
The activation energy represented on the energy diagram is as given as
"Activation energy is the distance from the reactant to the top of the hill"
So, the correct option is A.
What is activation energy?The minimum amount of energy required by the reactant to do the reaction is called activation energy.
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Given that there are more possible combinations for amino acids than amino acids themselves, what does this imply about the number of codes for each amino acid?
The fact that there are more possible combinations for amino acids than the number of amino acids themselves implies that each amino acid can be encoded by multiple codons.
A codon is a sequence of three nucleotides in DNA or RNA that corresponds to a specific amino acid.
There are 20 standard amino acids used to build proteins in living organisms. However, there are 64 possible three-letter combinations of nucleotides (4³) that can be used to form codons. This means that on average, there are more than three codons that can encode each amino acid.
To calculate the number of codons per amino acid on average, we divide the total number of codons (64) by the number of amino acids (20). Therefore, the average number of codons per amino acid is 64/20 = 3.2.
This indicates that there is a degeneracy or redundancy in the genetic code, where multiple codons can specify the same amino acid.
For example, the amino acid leucine is encoded by six different codons (UUA, UUG, CUU, CUC, CUA, CUG), while methionine and tryptophan are each encoded by a single codon.
In conclusion, the existence of more possible combinations for amino acids than amino acids themselves means that the genetic code is degenerate, allowing for redundancy and flexibility in protein synthesis.
This redundancy helps to protect against errors in DNA replication and transcription and allows for evolution to occur through the accumulation of genetic variations.
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28. A runner completes a 10 km run in about 30 minutes. What was the runner's average
speed in km/h? Hint: (60 minutes = 1 hr)
a. 10 km/hr
c. 20 km/hr
b. 15 km/hr
d. 30 km/hr
Answer:
20 km/h
Explanation:
Speed = distance ÷ time
Speed = 10 ÷ 0.5 hours
Speed = 20 km/hr
Describe reflection, refraction, and absorption.
Answer:
Refraction is the bending of a wave when it enters a medium where its speed is different, like going from the air (gas) to a glass of water (liquid). Absorption is when light energy penetrates an object. Typically this energy is then converted to heat.
Molecular compounds of low molecular weight tend to be gases at room temperature. Which of the following is most likely to not be a gas at room temperature? A CL2, B HCL, C LiCL, D H2, E CH4.
Molecular compounds of low molecular weight tend to be gases at room temperature. LiCl is most likely to not be a gas at room temperature. The correct answer is C.
LiCl is a salt, which is an ionic compound. Ionic compounds are held together by strong electrostatic forces between the oppositely charged ions.
These forces are much stronger than the forces that hold together molecular compounds, which are held together by covalent bonds. As a result, ionic compounds have much higher melting and boiling points than molecular compounds.
At room temperature, LiCl is a solid. It has a melting point of 613 degrees Celsius and a boiling point of 1360 degrees Celsius.
The other compounds listed in the question are all molecular compounds. They have much lower melting and boiling points than LiCl. At room temperature, they are all gases.
Cl₂ has a melting point of -101 degrees Celsius and a boiling point of -34 degrees Celsius.
HCl has a melting point of -85 degrees Celsius and a boiling point of -85 degrees Celsius.
H₂ has a melting point of -259 degrees Celsius and a boiling point of -253 degrees Celsius.
CH₄ has a melting point of -182 degrees Celsius and a boiling point of -164 degrees Celsius.
Therefore, the correct option is C, LiCl.
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Which of the following accurately describes the primary species in solution at point A on the titration curve for the titration of HF with NaOH? pH A) HF D B) HF and OH C) OH B D) F mL OH-
At point A on the titration curve for the titration of HF with NaOH, the primary species in the solution is HF.
This is because at the beginning of the titration before any NaOH is added, the solution consists primarily of the acid being titrated, which in this case is HF.
As NaOH is slowly added, it reacts with HF in a 1:1 stoichiometric ratio to form water and the conjugate base of HF, F-. However, at point A, the amount of NaOH added is still very small, so the majority of the original HF remains unreacted.
The presence of OH- ions from NaOH is not significant enough at this point to affect the overall pH of the solution. Therefore, the primary species at point A is HF.
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A sample of 0.2140 g of an unknown monoprotic acid was dissolved in 25.0 mL of water and titrated with 0.0950 M NaOH. The acid required 27.4 mL of base to reach the equivalence point.
What is the molar mass of the acid?
After 15.0 mL of base had been added in the titration, the pH was found to be 6.50. What is the Ka for the unknown acid?
The molar mass of the acid is 82.0 g/mol. The Ka of the unknown acid is 1.69 × 10⁻⁶.
How to determine molar mass and Ka?Molar mass of the acid:
The molar mass of the acid can be calculated using the following equation:
Molar mass = mass / moles
The mass of the acid is 0.2140 g and the moles of the acid can be calculated using the following equation:
moles = volume × concentration
The volume of NaOH used to reach the equivalence point is 27.4 mL and the concentration of NaOH is 0.0950 M.
moles of NaOH = 27.4 mL × 0.0950 M = 2.613 mmol
Since the acid and NaOH react in a 1:1 ratio, the moles of the acid is also 2.613 mmol.
Substituting these values into the first equation:
Molar mass = 0.2140 g / 2.613 mmol = 82.0 g/mol
Ka for the unknown acid:
The Ka for the unknown acid can be calculated using the following equation:
Ka = [H⁺][A⁻] / [HA]
where:
Ka is the acid dissociation constant
[H⁺] is the concentration of hydrogen ions
[A⁻] is the concentration of the conjugate base
[HA] is the concentration of the acid
The concentration of hydrogen ions can be calculated using the pH. The pH of the solution after 15.0 mL of base had been added is 6.50.
pH = -log[H⁺]
6.50 = -log[H⁺]
[H⁺] = 10^-6.50
[H⁺] = 3.162 × 10⁻⁷ M
The concentration of the conjugate base can be calculated using the following equation:
[A-] = moles of A- / volume of solution
The moles of A⁻ = the moles of NaOH added after 15.0 mL, which is 1.438 mmol. The volume of the solution is 25.0 mL + 15.0 mL = 40.0 mL.
[A⁻] = 1.438 mmol / 40.0 mL
[A⁻] = 3.595 × 10⁻³ M
The concentration of the acid can be calculated using the following equation:
[HA] = moles of HA / volume of solution
The moles of HA = the moles of acid, which is 2.613 mmol. The volume of the solution is 40.0 mL.
[HA] = 2.613 mmol / 40.0 mL
[HA] = 6.532 × 10⁻³ M
Substituting these values into the Ka equation:
Ka = (3.162 × 10⁻⁷ M)(3.595 × 10⁻³ M) / (6.532 × 10⁻³ M)
Ka = 1.69 × 10⁻⁶
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using standard reduction potentials from the aleks data tab, calculate the standard reaction free energy ΔGD for the following redox reaction. round your answer to 3 significant digits.
I2 (s) + 6H20 (l) + 5Br2(l) --> 2IO3- (aq) + 12 H+ (aq) + 10 Br- (aq)
To calculate the standard reaction free energy (ΔG°) for the given redox reaction, we need to use the standard reduction potentials from the ALEKS data tab.
To calculate the standard reaction free energy (ΔG°) for the given redox reaction, we need to utilize the standard reduction potentials (E°) of the involved species. The ΔG° is related to the standard reduction potentials through the equation: ΔG° = -nFΔE°, where n represents the number of electrons transferred and F is the Faraday constant.
Let's analyze the reaction and identify the half-reactions to determine the number of electrons transferred.
Half-reaction 1: I2(s) + 2e- → 2I- (aq)
Half-reaction 2: Br2(l) + 2e- → 2Br- (aq)
Half-reaction 3: 6H2O (l) → 12H+ (aq) + 6e-
Half-reaction 4: 2IO3- (aq) + 12H+ (aq) + 10e- → I2 (s) + 6H2O (l)
By comparing the half-reactions, we can see that 5 electrons are transferred in the reaction.
For the oxidation reactions:
2IO3- (aq) + 12H+ (aq) + 10Br- (aq) → I2 (s) + 6H2O (l) + 5Br2 (l): coefficient = 1
Now we can calculate ΔGᴰ:
ΔGᴰ = (1 * E°(I2/I-)) + (5 * E°(Br2/Br-)) + (3 * E°(H2O/O2)) - (1 * E°(IO3-/H2O/Br2))
Substituting the values:
ΔGᴰ = (1 * 0.536 V) + (5 * 1.087 V) + (3 * 1.229 V
ΔE° = E°(half-reaction 4) - [E°(half-reaction 1) + E°(half-reaction 2) + E°(half-reaction 3)]
After obtaining ΔE°, we can calculate the standard reaction free energy (ΔG°) using the equation ΔG° = -nFΔE°. Since we know n = 5 and F is a constant, we can substitute these values into the equation to calculate ΔG°.
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How are traits passed down through generations?
What is the Ka of a 0.0981 M
solution of hydrocyanic acid
(HCN) with a pH of 6.00?
Ka = [?] x 10!?)
Answer:
Attached picture
Ka = [?] x 10
1.02 x 10^-11 = [?] x 10
[?] = 1.02 (I'm assuming you're asking this)
(If not then divide the 10)
Answer:
The answer is 1.02x10^-11
Explanation:
Fill in the box 1.02 and then -11
Hello Friends Can Yall Plz Help Me For Brainliest Don’t Comments No B.S Yu Will Get Cursed out show ya work
Answer:
it is b
Explanation:
mid ocean ridge diverges meaning it moving in two different direction horizontally - left to right
1 MLR3 → 1 MR + 1 LR2
If 23.5 grams of MLR3 react, how many moles of MR are produced?
A gas mixture is made by combining 5.5 g each of Ar, Ne, and an unknown diatomic gas. At STP, the mixture occupies a volume of 70.31 L. What is the molar mass of the unknown gas? molar mass: g/mol Identify the unknown gas. OF2 B. 02 C. CI, D. H2 E. N2
H2 is the unknown gas if a gas mixture is made by combining 5.5 g each of Ar, Ne, and an unknown diatomic gas and at STP, the mixture occupies a volume of 70.31 L.
Why is there volume in gas?
Because their molecules are very loosely packed, contain wide intermolecular gaps, and move about, gases lack a distinct shape or volume. Because there is little to no attraction between molecules, gases can take on any shape or volume.
One mole of gas will take up 22.4 litres at typical conditions (0 °C and 1 atm). No matter what kind of petrol is being used, this is true. Since the relationship between volume and the number of moles of a gas is linear, two moles of any gas at STP should have twice the volume of one mole.
The total number of moles of Ar, Ne, and unknown gas, each with a mass of 7g, in the gas mixture is
= (5.5/40 + 5.5/20 + 5.5/m) mol
Total volume of all gases at STP:
(5.5/40 + 5.5/20 + 5.5/m) mol * 22.4 L/(mol) = 70.31L
(5.5/40 + 5.5/20)+ 5.5/m = 70.31L/ 22.4L
5.5/m = 3.19 -0.4125
m = 1.98 ≈ 2g/mol i.e. H2
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Rank the following fatty acids a coording to their melting point, from highest melting point to lowest melting point. Rank from highest melting point to lowest melting point. To rank items as equivalent, overlap them.
The ranking of the given fatty acids according to their melting point is Stearic acid > Palmitic acid > Lauric acid > Myristic acid > Oleic acid > Linoleic acid.
1. Stearic acid: Stearic acid has a long chain of 18 carbon atoms with no double bonds, resulting in a tightly packed structure. It has the highest melting point among the given fatty acids.
2. Palmitic acid: Palmitic acid also has a long chain of 16 carbon atoms with no double bonds. While it is slightly shorter than stearic acid, it still has a high melting point.
3. Lauric acid: Lauric acid contains 12 carbon atoms and no double bonds. It has a slightly lower melting point compared to palmitic acid and stearic acid.
4. Myristic acid: Myristic acid consists of 14 carbon atoms and no double bonds. It has a slightly lower melting point compared to lauric acid.
5. Oleic acid: Oleic acid is an unsaturated fatty acid with one double bond, located at the 9th carbon atom. It has a lower melting point compared to the saturated fatty acids listed above.
6. Linoleic acid: Linoleic acid is a polyunsaturated fatty acid with two double bonds, located at the 9th and 12th carbon atoms. It has the lowest melting point among the given fatty acids due to the presence of multiple double bonds, which disrupt the packing of the fatty acid chains.
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What is the mass of sulfuric acid, H2SO4, that is contained in 2.0 L of a 5.85 M solution ?
A-1147.44 grams
B- 0.12 grams
C-11.7 grams
D-98.07 grams
Se mezclan 20 gramos de agua (1cal/g°C) a 40 °C con 15 gramos de alcohol (0,58cal/g°C) a 30 °C. ¿Cuál ha sido la temperatura de equilibrio térmico?
Answer:
[tex]T_{EQ}=37\°C[/tex]
Explanation:
¡Hola!
En este caso, para los problemas de equilibrio térmico, consideramos que la energía liberada por la sustancia que inicialmente está caliente (agua), es absorbida por la sustancia que inicialmente está fría (alcohol); thus, we can write:
[tex]Q_{agua}=-Q_{alcohol}[/tex]
La cual puede ser escrita en términos de masa, calor specifico y temperaturas:
[tex]m_{agua}C_{agua}(T_{EQ}-T_{agua})=-m_{alcohol}C_{alcohol}(T_{EQ}-T_{alcohol})[/tex]
De este modo, al resolver para la temperature de equilibrio térmico, obtenemos la siguiente expresión:
[tex]T_{EQ}=\frac{m_{agua}C_{agua}T_{agua}+m_{alcohol}C_{alcohol}T_{alcohol}}{m_{agua}C_{agua}+m_{alcohol}C_{alcohol}}[/tex]
Así, al reemplazar los valores en esta, obtenemos:
[tex]T_{EQ}=\frac{(20g)(1cal/g\°C)(40\°C)+(15g)(0.58cal/g\°C)(30\°C)}{(20g)*(1cal/g\°C)+(15g)(0.58cal/g\°C)} \\\\T_{EQ}=37\°C[/tex]
¡Saludos!
The mixtures of sodium carbonate and calcium nitrate react to participate calcium carbonate and sodium nitrate. This reaction is shown by which balanced chemical equation?
Explanation:
Na2CO3+Ca(No3)2---> CaCO3+2NaNo3
How many grams of calcium carbonate, CaCO3, contain 48 grams of oxygen atoms?
A) 41
B) 50
C) 62
D) 88
E) 100
Answer:
(40 g O) / (15.99943 g O/mol) x (1 mol CaCO3 / 3 mol O) x (100.0875 g CaCO3/mol) =
83 g CaCO3
So answer D), although three significant digits are not justified.
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