Answer:
(A) Slipping and breaking
(B) Clean and dry
(C) Cracks
Explanation:
This describes the process of unpacking a glassware for use.
You should set out support like a cork ring or clamp (these are simple machines that'll hold the glassware in place) before removing the glassware from a glassware kit; to place the glassware in and to stop it from slipping and breaking.
Thoroughly check that the glassware is clean and dry and that it does not have any cracks, before using it.
6) Hydrogen gas can be generated from the reaction between aluminum metal and hydrochloric acid:
2 Al(s) + 6 HCl(aq) + 2 AICI3, (aq) + 3 H2(g)
a. Suppose that 3.00 grams of Al are mixed with excess acid. If the hydrogen gas produced is directly collected
into a 850 mL glass flask at 24.0 °C, what is the pressure inside the flask (in atm)?
b. This hydrogen gas is then completely transferred from the flask to a balloon. To what volume (in L) will the
balloon inflate under STP conditions?
c. Suppose the balloon is released and rises up to an altitude where the temperature is 11.2 °C and the pressure is
438 mm Hg. What is the new volume of the balloon (in L)?
Stoichiometry refers to the relationship between the moles of reactants and products.
This question must be solved using both stoichiometry and the gas laws
The reaction equation is;
2 Al(s) + 6 HCl(aq) --------> 2 AICI3, (aq) + 3 H2(g)
Using stoichiometryNumber of moles of Al = 3g/27g/mol = 0.11 moles
According to the reaction equation;
2 moles of Al yields 3 moles of H2
0.11 moles of Al yields 0.11 * 3/2 = 0.165 moles
Using the gas lawsFrom the ideal gas equation;
PV=nRT
P = ?
n= 0.165 moles
V = 0.85 L
T = 297 K
R = 0.082 atmLK-1mol-1
P= nRT/V
P = 0.165 * 0.082 * 297/0.85
P= 4.73 atm
Under STP conditions;P1 = 4.73 atm
T1 = 297 K
V1 = 0.85 L
P2 = 1 atm
T2 =273 K
V2 =?
From the general gas equation;P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 4.73 * 0.85 * 273/1 * 297
V2 = 3.69 L
P1 = 760 mmHg
T1 = 273 K
V1 = 3.69
P2 = 438 mm Hg
T2 = 284.2 K
V2 =?
P1V1/T1 = P2V2/T2
P1V1T2 = P2V2T1
V2 = P1V1T2/P2T1
V2 = 760 * 3.69 * 284.2/438 *273
V2 = 797010.48/119574
V2= 6.67 L
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Determine the number of moles of aluminum in 2.154 x 10-1 kg of Al. Group of answer choices 5816 mol 7.984 mol 6.02 X 1023 mol 4.801 mol 8.783
Answer:
Avogadro's number is 1 mol = 6.02 * 10^23 elements
It means that 1 mol of atoms is 6.02 * 10^23 atoms
1 mol of atoms = 6.02 * 10^23 atoms
From there, if you divide both sides by 1 mol of atoms, you get
1 = 6.02 * 10^23 atoms / 1 mol of atoms.
That means, that to pass from a number of moles of atoms to number of atoms you have to multipby by the conversion factor
6.02*10^23 atoms Al/ 1 mol Al
That is the second option of the list.
Explanation:
In the graphic, 195 represents the _______.
195 Pt
78
A. Atomic Mass
B. Atomic Number
C. Neutron Number
Answer:
ITS ANSWER IS
OPTION B. ATOMIC NUMBER
HI HAVE A NICE DAY
. Which of the following statement is not related to a chemical reaction ? A. New substances are formed B. Atoms of the elements transform into atoms of other elements C. The properties of the new substances will be different D. There will be bond breaking and bond forming
Answer:
the answer should be B because elements do not tranform into other elements in a chemical reaction
am I right please?
Consider the reaction: A(aq) + 2B (aq) === C (aq). Initially 1.00 mol A and 1.80 mol B
were placed in a 5.00-liter container. The mole of B at equilibrium was determined to
be 1.00 mol. Calculate K value.
0.060
5.1
25
17
Ugh
Answer:
17
Explanation:
Step 1: Calculate the needed concentrations
[A]i = 1.00 mol/5.00 L = 0.200 M
[B]i = 1.80 mol/5.00 L = 0.360 M
[B]e = 1.00 mol/5.00 L = 0.200 M
Step 2: Make an ICE chart
A(aq) + 2 B(aq) ⇄ C(aq)
I 0.200 0.360 0
C -x -2x +x
E 0.200-x 0.360-2x x
Then,
[B]e = 0.360-2x = 0.200
x = 0.0800
The concentrations at equilibrium are:
[A]e = 0.200-0.0800 = 0.120 M
[B]e = 0.200 M
[C]e = 0.0800 M
Step 3: Calculate the concentration equilibrium constant (K)
K = [C] / [A] × [B]²
K = 0.0800 / 0.120 × 0.200² = 16.6 ≈ 17
what is the bond energy required to break one mole of carbon-carbon bonds
Answer:
100 kcal of bond energy
Two common methods to generate an aldehyde is by oxidation of an alcohol and through ozonolysis.
a. True
b. False
Answer:
a. True.
Explanation:
Only primary and secondary alcohols can oxidise to give an aldehyde. But a weak oxidizing agent must be used to prevent formation of a carboxylic acid or ketone.
weak oxidizing agents: Chromyl chloride, silver/oxygen/500°C
take an example of ethanol:
[tex]{ \bf{CH _{3} CH_{2}OH \: \: \frac{Ag/O_{2} }{500 \degree C} > \: \:CH _{3} CHO}}[/tex]
[tex]{ \sf{CH _{3} CHO \: \: is \: ethanal}} [/tex]
By ozonolysis:
Here, reactants are Ozone gas, Carbon tetrachloride at a temperature (<20°C), ethanoic acid, zinc and water.
take an example of propanol:
if it undergoes ozonolysis, it gives ethanal and methanal.
Answer:
A. True
Explanation:
Only primary and secondary alcohols can oxidise to give an aldehyde. But a weak oxidizing agent must be used to prevent formation of a carboxylic acid or ketone.
weak oxidizing agents: Chromyl chloride, silver/oxygen/500°C
take an example of ethanol:
By ozonolysis:
Here, reactants are Ozone gas, Carbon tetrachloride at a temperature (<20°C), ethanoic acid, zinc and water.
take an example of propanol:
if it undergoes ozonolysis, it gives ethanal and methanal.
The mass of a container is determined to be 1.2 g. A sample of a compound is transferred to this container, and the mass of the compound plus the container is determined to be 3.06 g. The mass of the compound should be reported as:__.
Answer:
Sorry I don't know what you
According to law of conservation of mass as mass is neither created nor destroyed mass of compound should be reported as 1.86 g that is by subtracting mass of compound from mass of compound and container.
What is law of conservation of mass?According to law of conservation of mass, it is evident that mass is neither created nor destroyed rather it is restored at the end of a chemical reaction .
Law of conservation of mass and energy are related as mass and energy are directly proportional which is indicated by the equation E=mc².Concept of conservation of mass is widely used in field of chemistry, fluid dynamics.
Law needs to be modified in accordance with laws of quantum mechanics under the principle of mass and energy equivalence.This law was proposed by Antoine Lavoisier in the year 1789.
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If Sterling silver is 90.0% silver and 10.0% copper, what is the maximum amount of Sterling silver that can be made if you have 48.3 grams of silver metal and an unlimited amount of copper
Answer:
[tex]x=54g[/tex]
Explanation:
From the question we are told that:
Content of Sterling silver:
Let x be sterling silver
Silver [tex]S=0.9x[/tex]
Copper [tex]C=0.1x[/tex]
Total silver available [tex]T=48.3[/tex]
Generally the equation for Total amount to be made is mathematically given by
[tex]T=\frac{x*90}{100}[/tex]
[tex]x=\frac{48.3*100}{90}[/tex]
[tex]x=54g[/tex]
The sugars can be classified as either aldoses or ketoses.
a. True
b. Fasle
Write balanced equations for the reaction of each of the following carboxylic acids with NaOH. Part A formic acid Express your answer as a chemical equation. A chemical reaction does not occur for this question. Request Answer Part B 3-chloropropanoic acid Express your answer as a chemical equation. nothing A chemical reaction does not occur for this question.
Answer:
Part A
HCOOH(aq) + NaOH(aq) → HCOONa(aq) + H2O(l)
Part B
ClCH2CH2CO2H(aq) + NaOH(aq) ------> ClCH2CH2CO2Na(aq) + H2O(l)
Explanation:
The reaction between an alkanoic acid and a base is a neutralization reaction. The reaction occurs as follows;
RCOOH + NaOH ----> RCOONa + H2O
We have to note the fact that the net ionic reaction still remains;
H^+(aq) + OH^-(aq) ---> H2O(l)
In both cases, the reaction can occur and they actually do occur as written.
một chất hữu cơ có cấu tạo c2h2 cho khí br2 vào ta được hỗn hợp khí
Answer:
C2H2 + Br2 → C2H2Br2
Explanation:
how is the Sun classified?
A as a giant star
B as a medium star
C as a white star as a neutron star
D as a white dwarf
Answer:
As a giant star.
Explanation:
A
a. You have a stock solution of 14.8 M NH3. How many milliliters of this solution should you dilute to make 1000.0 mL of 0.250 M NH3?
b. If you take a 10.0 mL portion of the stock solution and dilute it to a total volume of 0.500 L, what will be the concentration of the final solution?
Answer:A) V = 16.892 ml
Explanation:
M1 * V1 = M2 * V2
14.8 M * V1 =0.250 M * 1000 ml
V1 = 16.892 ml
a. The volume of 16.89 milliliters of the stock solution of 14.8 M should be diluted to make 1000.0 mL of 0.250 M.
b. The concentration of the final solution is 0.296 M.
What is the dilution law?The concentration or the volume of the concentrated or dilute solution can be calculated by using the equation:
M₁V₁ = M₂V₂
where M₁ and V₁ are the concentration and volume of the concentrated solution respectively and M₂ and V₂ are the concentration and volume of the dilute solution.
A stock solution is a solution that has a high concentration and that will be diluted to a low concentration by the addition of water in it.
Given, a stock solution of concentration, M₁ = 14.8 M
The concentration of the diluted solution, M₂ = 0.250 M
The volume of diluted solution, V₂ = 1000ml
Substitute the value of the molarity and volume in equation (1):
(14.8)× (V₁) = (1000) × (0.250)
V₁ = 16.89 ml
Similarly, for part (b): M₁ = 14.8 M, V₁ = 10 ml and V₂ = 0.5L = 500 ml
(14.8)× (10) = (500) × (M₂)
M₂ = 0.296 M
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2. An ion is a charged particle that is formed when
a. An atom gains electrons
b. An atom loses electrons
c. Both A and B
d. None of the above
The correct answer is option c. Both A and B: An ion is a charged particle that is formed when an atom gains electrons or an atom loses electrons.
First you need to know the definition of ion. An ion is a molecule or atom that has a positive or negative electrical charge.
That is, an ion is an atom whose electric charge is not neutral. This charged particle can be positive or negative.
Ionization is the chemical or physical process by which ions are produced. In this process, negatively charged ions are produced by gaining electrons and are known as anions.
The positively charged are produced by the loss of electrons and are known as cations.
In summary, an ion is a charged particle that is formed when an atom gains electrons or an atom loses electrons, and they are known as cations and anions respectively.
The correct answer is both A and B.
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How did Kepler's discoveries contribute to astronomy?
O They supported the heliocentric model.
O They established the laws of planetary motion.
O They explained how the Sun rises and sets.
O They made astronomy accessible to people who spoke Italian.
They made astronomy accessible to people who spoke italian
Answer:
"They established the laws of planetary motion"
Explanation:
Mr. Kepler was the astronomer who came up with the "Laws of Planetary Motion."
Cho các quá trình và số liệu sau:
C(d,s) ⭢ C (g,s) (1) : ΔH0298 = - 1,9 kJ
ΔG0298 = - 2,87 kJ
C(g,s) + O2 (k) ⭢ CO2 (k) (2): ΔH0298 = - 393,5 kJ
a)Giải thích tại sao trạng thái chuẩn của C lại là C(g) mà không phải là C (d).
b)Tính ΔH0298 của phản ứng sau:
C(d,s) + O2 (k) ⭢ CO2 (k) (3)
ΔH0298 của phản ứng 3 có phải là ΔH0298, sinh nhiệt của CO2 không ? Tại sao?
Answer:
rrgggf in the world of the world of the world of the up the good morning I will take a user and pass it on the
the probability that it will rain tomorrow is 11/15. What is the probability that it will not rain ?
Answer:
4/15
Explanation:
15/15 - 11/15 = 4/15
If 11/15 is the probability that it'll rain tomorrow, then the rest should be the probability that it'll not rain tomorrow.
The elementary reaction 2H2O(g)↽−−⇀2H2(g)+O2(g) proceeds at a certain temperature until the partial pressures of H2O, H2, and O2 reach 0.0900 bar , 0.00100 bar , and 0.00350 bar respectively. What is the value of the equilibrium constant at this temperature?
Answer:
3.89 ×10^-5
Explanation:
Since they are gaseous reactants, we obtain the equilibrium constant from the given partial pressures;
p(H2O) = 0.0900 bar
p(H2) = 0.00100 bar
p(O2) = 0.00350 bar
The equation of the reaction is;2H2O(g)⇄2H2(g)+O2(g)
Kp= p(H2) . p(O2)/p(H2O)
Kp= 0.00100 × 0.00350/0.0900
Kp= 3.89 ×10^-5
A central atom has two lone pairs on opposite sides and four single bonds. What is the molecule geometry of the result?
A. octahedral
B. tetrahedral
C. square planar
D. linear
The correct answer is C. square planar
According to the Valence Shell Electron Pair Repulsion Theory(VSEPR), The shape of a molecule depends on the number of electron pairs in the molecule.
VSEPR theory was first coined by Gillespie and Nyhlom in 1957 as an improvement over the Sidgwick - Powell theory.
According to this theory, the shape of a molecule is determined by the number of electron pairs that surround the valence shell of the central atom in the molecule. The electron pairs are positioned as far apart in space as possible to minimize repulsion of electron pairs.
However, the presence of lone pairs distorts the shape anticipated for the molecule on the basis of VSEPR.
For a molecule having six electron pairs, an octahedral geometry is expected(electron domain geometry). However, the presence of two lone pairs which are positioned at opposite side of the four single bonds leads to an observed square planar molecular geometry.
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Answer:
square planar
Explanation:
Benzoyl chloride undergoes hydrolysis when heated with water to make benzoic acid. Reaction scheme of benzoyl chloride with water and heat over the arrow, and benzoic acid and hydrochloric acid as products. Calculate the molar mass of the reactant and product. Report molar masses to 1 decimal place.
Answer:
The molar mass of benzoic acid is 122.1 g/mol
The molar mass of hydrochloric acid = 36.5 g/mol
Explanation:
Benzoyl chloride is an organic compound with the molecular formula C₆H₅COCl. It is an acyl chloride since is it an organic derivative of a carboxylic acid. Acyl chlorides have the general molecular formula, R-COCl, where R is a side chain.
The R group of benzoyl chloride is the benzyl group C₆H₅. It reacts with water (hydrolysis) to produce hydrochloric acid and benzoic acid. The equation of the reaction is given below:
C₆H₅COCl + H₂O → C₆H₅CO₂H + HCl
The molar mass of benzoic acid as well as of hydrochloric acid is calculated from the sum of the masses of the atoms of the elements present in the compound thus:
Molar mass of carbon = 12.0107 g
Molar mass of hydrogen = 1.00784 g
Molar mass of oxygen = 15.999 g
Molar mass of chlorine = 35.453 g
Molar mass of benzoic acid, C₆H₅CO₂H containing 7 moles of atoms of carbon, 6 moles of atoms of hydrogen and 2 moles of atoms of oxygen = 7 × 12.0107 + 6 × 1.00784 + 2 × 15.999 = 122.1 g
Therefore, the molar mass of benzoic acid is 122.1 g/mol
Molar mass of hydrochloric acid, HCl, containing 1 mole of atoms of hydrogen and 1 mole of atoms of chlorine = 1 × 1.00784 + 1 × 35.453 = 36.5 g
Therefore, the molar mass of hydrochloric acid = 36.5 g/mol
Each 5-ml teaspoon of Extra Strength Maalox Plus contains 450 mg of magnesium hydroxide and 500 mg of aluminum hydroxide. How many moles of hydronium ions H3O are neutralized by 1 teaspoon of antacid product?
Answer:
0.0347 moles of hydronium ions
Explanation:
The equation of the neutralization reaction between hydroxide and hydronium ions is given below:
H₃O+ (aq) + OH- (aq) ----> 2 H₂O (l)
From the equation above, 1 mole of hydroxide ions will neutralize one mole hydronium ions.
The moles of hydroxide ions present in 1 teaspoon or 5 mL of antacid product is calculated as follows:
Number of moles = mass / molar mass
Molar mass of Magnesium hydroxide, Mg(OH)₂ = 58 g/mol
Molar mass of aluminium hydroxide, Al(OH)₃ = 78 g/mol
Mass of magnesium hydroxide = 450 g = 0.45 g
Mass of aluminium hydroxide = 500 mg = 0.5 g
Moles of magnesium hydroxide = (0.45/58) moles
Moles of aluminium hydroxide = (0.5/78) moles
Equation of the ionization of magnesium hydroxide and aluminium hydroxide is given below:
Mg(OH)₂ (aq) ----> Mg²+ (aq) + 2 OH- (aq)
Al(OH)₃ (aq) ---> Al³+ (aq) + 3 OH- (aq)
Number of moles of hydroxide ions present in (0.45/58) moles of magnesium hydroxide = 2 × (0.45/58) moles = 0.0155 moles
Number of moles of hydroxide ions present in (0.5/78) moles of aluminium hydroxide = 3 × (0.5/78) moles = 0.0192 moles
Total moles of hydroxide ions = 0.0155 + 0.0192 = 0.0347 moles hydroxide ions
Therefore, 0.0347 moles of hydroxide ions will neutralize 0.0347 moles of hydronium ions.
A chunk of a metal alloy displaces 0.58 L of water and has a mass of 2.9 kg. What is the density of the alloy in g/cm3?
Answer:
5g/cm3
Explanation:
firstly convert the litres and kilograms to grams and centimeters.
1l is equivalent to 1000cm3
0.58×1000
580cm3
and 1kg is equivalent to 1000g
2.9×1000
2900
then find the density by using the formula
density=mass/volume
=2900g/580cm3
=5g/cm3
I hope this helps
A natural element consists of two isotopes: Cl-35 and Cl-37. The composition of these two isotopes differs by:
Answer:
There are no options in this question, however, it can be answered based on general understanding
- The number of neutrons each isotope contain
Explanation:
Isotopes are atoms of an element with the same atomic number or number of protons but different mass number/atomic masses. Since isotopes have same proton numbers, they have similar chemical behavior or identity.
However, difference in atomic mass or mass number of the same atomic number indicates that the number of neutrons each isotope contain differs from one another. Hence, in two isotopes of chlorine given as follows: Cl-35 and Cl-37, the NUMBER OF NEUTRONS in each atom differentiates the two isotopes.
Cl-35 contains 18 neutrons while Cl-37 contains 20 neutrons.
Consider an equilibrium (K1) that is established after 10 mL of compound A and 10 mL of compound B are mixed. Now, imagine the equilibrium (K2) where 1 mL of compound A is added to 100 mL of compound B. How are K1 and K2 related algebraically (read this question VERY carefully, at least one more time)
The equilibrium constant K₁ = Equilbrium constant K₂.
The equilibrium constant, K, of a reaction, is defined as:
"The ratio between concentration of products powered to their reaction quotient and concentration of reactants powered to thier reaction quotient".
For the reaction:
aA + bB ⇄ cC + dD
The equilibrium constant, K, is:
[tex]K = \frac{[C]^c[D]^d}{[A]^a[B]^b}[/tex]
Now, assuming the reaction of the problem is 1:1:
A + B ⇄ C + D
[tex]K = \frac{[C][D]}{[A][B]}[/tex]
The concentrations of the reactants are directly proportional to the volume added. Thus, we can assume that concentration = Volume. Replacing for K₁ and K₂:
[tex]K_1 = \frac{[C][D]}{[10mL][10mL]} = K_1 = \frac{[C][D]}{100mL^2}[/tex]
In the same way:
[tex]K_2 = \frac{[C][D]}{[1mL][100mL]} = K_2 = \frac{[C][D]}{100mL^2}[/tex]
Thus, we can say:
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Draw a formula for Thr-Gly-Ala (T-G-A) in its predominant ionic form at pH 7.3. You may assume for the purposes of this question that the pKa values of the acidic groups of amino acid residues in the peptide are the same as in the amino acid itself.
Answer:
gggggggggg
Explanation:
gggggggg
The tripeptide formed from threonine, glycine and alanine is neutral at the pH of 7.3. The carboxylic end is negative charged by donating its proton to form the NH₃⁺ group.
What is peptide?Peptides are protein units formed from two or more amino acids bonded through peptide bonds. There are essential and non-essential amino acids. Essential amino acids have to be uptake from food and non-essential amino acids are synthesized inside the body.
Threonine is an essential amino acid with a CH₃CHOH side group. Glycine has the simplest side group hydrogen and alanine has CH₃ side chain. Both glycine and alanine are non-essential amino acids.
Each amino acids are represented with a three letter code or one letter symbol. Thus threonine is T, G for glycine and A for alanine. At a pH of 7.3 the peptide formed from these amino-acids contains a negatively charged carboxylic end.
A positively charged amino end made by protonation from the acid group make the overall charge zero. The structure of the peptide is given in the uploaded image.
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Compare and contrast the quantum mechanical model and Niels Bohr of the atom
Answer:
the quantum mechanical model VS. Neils Bohr of the atom
Explanation:
The Bohr model and quantum model are models that explain the structure of an atom. ... The key difference between Bohr and quantum model is that Bohr model states that electrons behave as particles whereas quantum model explains that the electron has both particle and wave behavior.
Forcus on the yellow highlighted texts, your help is appreciated.
[tex]{ \sf{ \red{no \: pranks}}}[/tex]
Answer:
Transition temperature is the temperature at which a substance changes from one state to another.
Allotropy is the existence of an element in many forms.
When hydrogen gas reacts with oxygen gas, water vapour is formed according to the
reaction 2H2 + O2 2H2O. If 3.00 mol of hydrogen gas react with 3.00 mol
of oxygen gas, which reactant will be the reactant in excess?
Explanation:
here's the answer to the question
What is the mass percentage of C in CH₃CH₂OH? Provide an answer to two decimal places.
Answer:
here's your answer
Explanation:
Molar mass of CH3CH2OH = 46.06844 g/mol
This compound is also known as Ethanol.
Convert grams CH3CH2OH to moles or moles CH3CH2OH to grams
Molecular weight calculation:
12.0107 + 1.00794*3 + 12.0107 + 1.00794*2 + 15.9994 + 1.00794
Percent composition by element
Hydrogen H 1.00794 6 13.128%
Carbon C 12.0107 2 52.143%
Oxygen O 15.9994 1 34.730%
The mass percentage of C in CH₃CH₂OH is 52.14% (to two decimal places)
To calculate the mass percentage of C (Carbon) in CH₃CH₂OH (Ethanol),
First, we will determine the mass of CH₃CH₂OH
Molar mass of CH₃CH₂OH = 46.07 g/mol
Mass of C = 12.01 g/mol
Now, for the mass percentage of C in CH₃CH₂OH,
We will determine the ratio of the total mass of C to the mass of CH₃CH₂OH, and then multiply by 100%
Since we have 2C in CH₃CH₂OH
Then, total mass of C in CH₃CH₂OH = 2 × 12.01 g/mol = 24.02 g/mol
That is,
Mass percentage of C in CH₃CH₂OH = [tex]\frac{24.02}{46.07} \times 100\%[/tex]
Mass percentage of C in CH₃CH₂OH = 0.5213805 ×100%
Mass percentage of C in CH₃CH₂OH = 52.13805%
Mass percentage of C in CH₃CH₂OH ≅ 52.14%
Hence, the mass percentage of C in CH₃CH₂OH is 52.14% (to two decimal places)
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