The mass of oxygen in 4 moles of C2H4O2 is 128g.
How to calculate mass?The mass of a substance can be calculated by multiplying the number of moles of the substance by its molar mass.
Molar mass of C2H4O2 = 12(2) + 1(4) + 16(2) = 60g/mol
mass of C2H4O2 = 60g/mol × 4 moles = 240grams
However, the mass of oxygen in the compound can be calculated as follows:
molar mass of oxygen/molar mass of compound × 240 grams
32g/mol ÷ 60g/mol × 240g
= 128g
Therefore, the mass of oxygen in 4 moles of C2H4O2 is 128g.
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How do I write the molecular and empirical formulas for compounds?
Answer: In order to write the formula of a binary molecular compound, use the prefixes to determine the subscript of each element. Write the symbols for the elements with the subscripts. Ionic and molecular compounds differ in composition—ions form ionic compounds, and molecules form molecular compounds.
In order to find a whole-number ratio, divide the moles of each element by whichever of the moles from step 2 is the smallest. If all the moles at this point are whole numbers (or very close), the empirical formula can be written with the moles as the subscript of each element.
Select the correct answer.
The given compatibility chart shows how different chemicals react with one another. In addition to heat generation, what chemical interaction consequence will likely occur between sulfuric acid and tetrazine?
No. Chemical Name
10 ammonium hydroxide
1 boric acid
16 benzene
6 butyramide
7 dimethyl amine
5 formaldehyde
3 formic acid
4 methanol
16 methyl ethyl ketone
7 pentylamine
10 sodium hydroxide
2 sulfuric acid
8 tetrazine
12 thiram
A.
violent polymerization
B.
innocuous and non-flammable gas generation
C.
toxic gas formation
D.
fire
The consequence of the reaction between sulfuric acid and tetrazine is fire. Option D
How does sulfuric acid react with tetrazine?The compound tetrazine is a basic compound that is composed of four atoms of hydrogen and two atoms of carbon. The formula of the compound is [tex]C_{2} H_{2}N_{4}[/tex] . The compound is a six membered ring that could react with acids and become decomposed. In all cases of the decomposition of the tartazine the reaction is a violent one that leads to the evolution of flames.
In this case, we have been told that there is a reaction between sulfuric acid and tetrazine. This is a very violent reaction that would result in the charring of the substrate.
Thus, when there is a chemical interaction between sulfuric acid and tetrazine, the result is fire.
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Use the equation to answer the question.
hydrogen + oxygen → water
H₂+O2 → 2H₂O
Which are the reactants in this equation?
(1 point)
A. oxygen and water
B. hydrogen and oxygen and water
water only
C. hydrogen and oxygen
Answer:
Hydrogen and oxygen
Explanation:
1: they react with each other to form the products
2: they are written on the left side of the equation
(c) In addition to the number of moles of CuSO4 calculated in part (b), what other quantity must be measured in order to calculate the mass percentage of CuSO4 in the impure sample of CuSO4(s)?
(b) This question is incomplete. To determine how many moles of CuSO4 are present in the impure sample, however. The following formula may be applied
moles = mass of CuSO₄ in impure sample ÷ molar mass of CuSO₄
(c) This question is also incomplete. , to calculate the mass percentage of CuSO₄ present in the impure sample of CuSO₄, the formulato be used is :
Mass percentage of CuSO₄ =mass of CuSO₄ present in the impure sample divide by mass of impure CuSO₄ × 100
Since the actual mass of the CuSO4 contained in the impure sample had to be determined before determining the number of moles, the mass of the impure sample must also be measured.
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64.9 grams of potassium chloride are reacted with excess oxygen to produce potassium chlorate, according to the reaction: KCl + O 2 → KClO 3 If 77.1 grams are produced, what is the percent yield of this reaction?
The percent of the yield of this reaction is 106.7 grams or 72.3%.
The reaction in question is a decomposition reaction. A decomposition reaction is a reaction in which a compound is broken down by the action of heat, light or electrical energy to produce two or more new substances. Here, potassium chlorate decomposes into potassium chloride and oxygen gas. This is the first part of the answer. This 0.506 mol of KCL is formed when 62 g of KCL 03 of Part B is reacted.
To express the efficiency of a reaction the percent yield can be calculated using the following formula: % Yield = Actual Yield/Theoretical Yield x 100. Percent Yield of 90% Rates means 90% and 10% responses. % of material that was efficient was wasted did not react or product was not captured. The yield rate is the difference between the actual amount of product produced and the calculated maximum yield. The formula for percent yield is the experimental yield divided by the theoretical yield and multiplied by 100.
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Can u please tell me the answer for the last two questions
(3)
This finding and the lack of syrinx in non-avian dinosaur fossils of the same age suggest that this organ may have developed later in the evolution of birds and that other dinosaurs may not have been able to produce sounds akin to those of modern birds.
We have discovered that birds are living theropod dinosaurs, a category of predatory creatures that includes velociraptor, by examining fossil evidence from the skeletons, eggs, and soft tissue of birdlike dinosaurs and primordial birds.(4)
Without sound, we couldn't hear, which would prevent us from speaking. Animals obviously cannot speak human language, but they are nevertheless capable of efficient communication. They can communicate across great distances by groaning, sobbing, shrieking, etc., and deliver vital messages that might be essential to their survival and well-being.
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The average dosage of oxcarbazepine for an epileptic child between the ages of 4 and 16 is 9.00 mg per 1 kg of body weight (9.00 mg/kg ). Calculate how many milliliters of oxcarbazepine a child who weighs 47.1 pounds should be prescribed considering the medication is served as a suspension of 60.0 mg/mL . Keep in mind that 1 pound is equivalent to 0.453 kilograms.
An oddly shaped mineral ore chunk has a mass of 43.88 g. If the ore is placed in a graduated cylinder filled initially to 20.1 mL with water, and then rises to a volume of 45.2 mL, the volume of the ore chunk is
mL, and its density is
g/mL.
The volume of the ore chunk is 25.1 mL, and its density is 1.748 g/ml.
Density is the substance's mass in line with a unit of volume. The image most usually used for density is ρ, even though the Latin letter D also can be used.
The density of a liquid is a measure of the way heavy it's far for the amount measured. in case you weigh identical quantities or volumes of two extraordinary drinks, the liquid that weighs more is greater dense. If a liquid that is less dense than water is lightly introduced to the floor of the water, it'll glide at the water.
mass of mineral ore is = 43.88 g
The initial volume of the cylinder = 20.1 mL
The final volume of the cylinder after the ore is placed = 45.2 mL
So, the actual volume of the ore is = 45.2 mL - 20.1 mL
= 25.1 mL
Therefore the density of the ore is = mass/volume
= 43.88 g / 25.1 mL
= 1.748 g/ml
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A quantum of energy has an energy of 4.14 x 10-14 J. Find the frequency of this radiation. Show your work.
The frequency of this radiation of a quantum of energy 4.14 *10-14 J is calculated to be 2.58 *10-15 Hz.
The Photoelectric Effect occurs when electrons are released from a metal surface when light strikes it. It was once thought that the greater the intensity of incoming light, the greater its energy, independent of hue. The light was viewed and treated as a wave, however, the wave phenomenon could not explain light's photoelectric actions.
The Quantum, according to Max Planck, is the smallest unit of energy that is released or absorbed in the form of electromagnetic radiation. The energy released or absorbed is proportional to the frequency of the radiation. It may be expressed mathematically as:
E= hc/λ
or
E= hf ( because, f = c/λ)
where,
E= Energy of the particle
h= Planck's constant
c= speed of light
λ= wavelength of the particle
f = frequency of the radiation
Thus, E= hf
Given,
E = 4,14*10-14J
E= 1.71017356 * 10^20 eV
h= 6.626 *10-34 m2Kg/s
E=hf
f= E/h
f= (1.71017356 * 10^20 eV) / (6.626 *10-34 m2Kg/s)
f= C
Thus, the frequency of this radiation is 6.626 *10-34 m2Kg/s.
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When humans exhale we release water vapor (H2O) . Water can then be broken down into hydrogen and oxygen. What is the chemical equation showing this process
Answer:
I think its catabolic reactions.
Explanation:
Well because in catabolic reactions, bonds are broken in larger molecules and energy is released. In cellular respiration, bonds are broken in glucose, and this releases the chemical energy that was stored in the glucose bonds.
For equal masses the
substance occupies the smaller volume.
For equal masses of a set of substances, the substance with the lightest unit mass will occupy the most volume.
his is further explained below.
What is mass?Generally, A physical body's mass may be defined as the amount of matter that it contains. Additionally, it is a measurement of the body's inertia, which is the resistance to acceleration when a net force is applied to the system.
A volume is a measurement of the amount of space that is occupied in three dimensions.
In conclusion, When all of the individual masses of a group of substances are the same, the one that has the lowest unit mass will take up the most space.
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The substance occupies a smaller volume
In equivalent masses, the substance occupies smaller volume?Mass is the quantity of matter an object contains, while the volume is much space take a hold of up. Example: A bowling ball and a basketball are much the same volumes as each other, but the bowling ball has substantially more mass. Volume is the quantity of area occupied by a substance, while mass is the amount of matter it carry. The amount of mass per unit of volume is a sample's substance. Volume is the size of the capacity that an object holds. For example, if a cup can hold 100 ml of water up to the peak, its volume is said to be 100 ml. Volume can also be defined as the amount of space occupied by the 3-dimensional object.
so we can conclude the substance occupies a smaller volume,
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Need help filling out sections B-E not sure if I did the calculations correctly. Am I only suppose to use the initial concentration values to solve? I just need help overall. Please and thank you.
Calculated Molarity of KMno4- Calculations are preferred in 4 significant figures
A1 =0.0195 M
A2= 0.0193 M
A3= 0.0148 M
A =Average = Sum/3 = 0.0179
Standard deviation calculation:
= Sqr root[{ (sqr (A-A1) + Sqr (A-A2) +sqr (A-A3) } / 3 ]
= 0.0022.
The concentration of solutes is of great importance in the study of chemical reactions because it determines the frequency with which molecules in solution collide, indirectly determining reaction rates and equilibrium conditions. See chemical equilibrium. Concentration can be expressed in many ways. Solution concentration is defined as the amount of solute present in a given volume of solution. Divide the mass of the solute by the total volume of the solution. Write down the formula C = m/V. where m is the mass of the solute and V is the total volume of the solution.
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climate change is one of the greatest threats humankind has known. Identify two reasons how forests can be part of the solution to this environmental catastrophe?
Answer:
One reason: Trees absorb CO2 for photosynthesis which reduces the amount of CO2 in the atmosphere. In return the trees provide us with oxygen which is one of the products of photosynthesis.
Second reason: Trees are good carbon storers
Explain the ecosystem of Himalayan region and its related aspects
The westernmost portion of the subtropical belt is home to the Himalayan subtropical pine forests, which are dominated by the Chir pine (Pinus roxburghii).
What region are included in Himalayan ?Although the Himalayan region, which includes Bhutan, Nepal, northern India, Pakistan, and the Tibet Autonomous Region, is known for its mountainous topography, it also exhibits a remarkable amount of ecological diversity.
The mountains' altitude, slope, and aspect, their intricate glaciology and hydrology, as well as the climate and microclimates that the range itself shapes, all contribute to this diversity. It is visible in grasslands, temperate, tropical, and subtropical forests, as well as glacial lake and river systems, high altitude deserts, and montane regions. The region's diversity of people matches that of its ecosystem.
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10. Balance the redox equations
a) SnO₂ + H₂ → Sn + H₂O
Answer:
SnO2 + 2H2 → Sn + 2H2O
Explanation:
Cassiterite + Tritium = Tin + Water
1 mole of Cassiterite [SnO2] reacts with 2 moles of Tritium [H2] to form 1 mole of Tin [Sn] and 2 moles of Water [H2O]
Answer:
Its simple,
Explanation:
The reaction will be as follows:
2SnO2 + 4H2 -->2Sn + 4H2O
The no. Between the elements are at the bottom.
What were the constants?
(1) Same puzzle
All of the participants were tested with the
same puzzle.
* It would not have been a fair test if some
had an easy 30 piece puzzle and some had a
harder 500 piece puzzle.
* Other constants: (2) same
(4) same person
experiment
(3) same
the
1) Due to the fact that we are initially uncertain of the distribution of the parent population from which our sample was collected.
2) The second question is incomplete, thus I am unable to answer it.
Therefore, it is advisable to only use one sample when doing non-parametric tests like the sign test or Wilcoxon sign test (depending upon the choice of the researcher).
A physical constant, also known as a basic physical constant or universal constant, is a physical number that is often believed to be both universal in nature and to have a constant value across time. In contrast, it is described by a mathematical constant, which has a constant value but doesn't immediately call for any physical measurement.
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4. How an atom reacts chemically depends on how willing it is to share with others.
Answer: GoodMorning: ) ✨ How an atom reacts chemically depends on how willing it is to share electrons with others. So When copper is combined with another element, in it makes bronze, the first manmade metal alloy. Ok let me just explain it to u to make it easy 4 you to understand .
Explanation: So we should know that when An atom refers to the smallest, indivisible unit made up of matter and forms all chemical elements.
Hence, atoms are the fundamental building blocks of matter and they determine the structure of all chemical elements.
In Chemistry, an atom is made up of three (3) distinct subatomic particles and these include;
Protons.Neutrons.Electrons.Chemical reactivity determines how readily a chemical element bonds with other chemical elements by sharing its electrons with them.
As a general rule, how an atom reacts chemically is highly (largely) dependent on the number of valence electrons in the outermost shell of its atom.
In conclusion, the willingness of an atom to share electrons determines how it reacts chemically with others.
Have a Great Day: ) <3
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A 20 g piece of metal with a specific heat of .30 is at a temperature of 20C. A 30 g piece of metal with a specific heat of 1.5 is added and the final temperature for both is 80C. What was the initial temperature of the metal that was added?
Answer:
60c
Explanation:
80c-20c=60c i think I don't know
Answer:
2x – 3y = 11 …………….. (i)
x – 2y = – 12 …………….. (ii)
(ii) ⇒ x = 2y – 12 ……. (iii)
Substitute value of x from (iii) in (i), we get
2(2y – 12) + 3y = 11
⇒ 4y – 24 + 3y = 11
⇒ 7y = 35
⇒ y = 5
Substituting value of y = 5 in equation (iii), we get
4 = 2(5) – 12 = 10 – 12 = – 2
Hence, x = – 2, y = 5 is the required solution
Now, 5 = – 2m + 3
⇒ 2m = 3 – 5
⇒ 2m = – 2
⇒ m = – 1.
Fill in the missing information
Calculate the percent composition by mass of each element in LiClO3.
The percent composition of each element's mass in LiClO3 is as follows:
Percent Composition of Li =7.68%,
Percent Composition of Cl = 33.7%,
Percent Composition of O =53.1%.
Briefing:It is necessary to know the molar masses of the constituent parts. We have:
Molar Mass Li = 6.94 grams per mole
Molar Mass Cl = 30.45 grams per mole
Molar Mass O = 16 grams per mole
Molar Mass LiClO3 = 90.39 grams per mole
Percent Composition of Li:
Utilizing the molar masses of Li and the specified compound:
[tex]\% \mathrm{Li}=\frac{6.94 \frac{\mathrm{g}}{\mathrm{mol}}}{90.39 \frac{\mathrm{g}}{\mathrm{mol}}} \times 100[/tex]
%Li =7.68%
Percent Composition of Cl:
Using the molar mass of Cl and the molar mass of the given compound
[tex]\% \mathrm{Cl}=\frac{30.45 \frac{\mathrm{g}}{\mathrm{mol}}}{90.39 \frac{\mathrm{g}}{\mathrm{mol}}} \times 100[/tex]
%Cl = 33.7%
Percent Composition of O:
Utilizing the molar masses of O and the specified compound:
[tex]\% \mathrm{O}=\frac{3 \times 16 \frac{\mathrm{g}}{\mathrm{mol}}}{90.39 \frac{\mathrm{g}}{\mathrm{mol}}} \times 100[/tex]
%O =53.1%
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Please Help!! 10 points
What is the electron configuration for 1s22s22p63s2
Answer:
atomic no 12
Explanation:
it's name is MAGNESIUM
Answer:
it is magnesium element.
Classical, alchemical, medical and technological traditions were chemistry's forerunners. Identify the contributions which each of these made to the development of chemistry.
There are many contributions that all the mentioned fields have made to the development of chemistry.
What is the contribution of these fields to chemistry?
When you hear the word "alchemy," you might picture witches watching a pot of boiling liquid or sorcerers working in smokey labs or disorganized libraries. Despite these associations with myth and mysticism, alchemical observations claim to have played a significant part in the advancement of modern science.
In the past, alchemy referred to any study of nature. was an ancient philosophical and theological discipline that merged metalworking and chemistry. Physics, medicine, astrology, mysticism, spiritualism, and art were all included in alchemy.
Alchemy was a sacred practice as well as a scientific discipline. Many of its practitioners have altruistic motives. For instance, alchemists may be able to cleanse humans if they discover the secret to "purifying" base metals into gold. At the same time, alchemy has historically been associated with get-rich-quick schemes and plenty of alchemists have been exposed as frauds and impostors.
Nevertheless, a few alchemists were significant practitioners whose work laid the foundation for modern chemistry and medicine.
Therefore, there are many contributions that all the mentioned fields have made to the development of chemistry.
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For the reaction 2 C4H10 + 13 O2 >>>>> 8 CO2 + 10 H2O, if 59.60 g of CO2 is produced, how much C4H10 was needed? Answer should include 2 decimal places.
19.673g Mass of C4H10 needed to produce 59.60 g of CO2
2C4H10 + 13O2 → 8CO2 + 10H2O
From this Balanced chemical equation we get that ;
2 mol C4H10 produce = 8 mol CO2
By using this relation we can solve given problem .
Mass of CO2 = 51.60 g
Moles of CO2 = Mass of CO2 / Molar mass of CO2
= 59.60 g / 44.01 (g/mol)
= 1.354 moles
now:
2 mol C4H10 produce = 8 mol CO2
So, X mol C4H10 produce = 1.354 mol CO2
X mol C4H10 =(2mol C4H10×1.354 mol)/8 mol CO2
= 0.3385 mol CO2
Moles of C4H10 =0.3385 mol
Mass of C4H10= Moles of C4H10 × Molar mass of C4H10
=0.3385mol × 58.12 (g/mol)
= 19.673 g
19.673g Mass of C4H10 needed
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How many significant figures is .0013
Answer: There are two significant figures because any zeros in front of non-zero numbers are not sig figs meaning that only the one and three count.
A hydrocarbon is burned producing 0.1467 g of carbon dioxide and 0.1201 g of water. What is the empirical formula of the hydrocarbon?
The empirical formula of given hydrocarbon is C1H4.
Finding the mass of C in CO2 and H in H2O is the initial stage in this process. This is accomplished by multiplying by the mass of the compound formed after dividing the atomic mass by the molecular mass.Making these masses into moles is the following stage. To do this, multiply the mass by the element's relative atomic mass.The last step is to multiply each of these two numbers by the smallest one, in this example, the quantity of moles of carbon.44g of CO2 → 1mol of carbon
∴0.1467g of carbon dioxide → 0.1467/44 = 0.0033 mol of C
18 g of water → 2mol of Hydrogen
∴ 0.1201 g of water = 2/18 × 0.1201. = 0.013 mol of H
molar ratio of C:H is 0.003 : 0.013
C:H = 1:4
Therefore empirical formula is C1H4
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converting grams and moles 45.5mg C6H6
1. 0.0455 grams
2. 0.582 moles
What is a mole?
A mole is just a measuring scale. In reality, it's one of the International System of Units' seven foundation units (SI). When already-existing units are insufficient, new ones are created. The levels at which chemical reactions frequently occur exclude the use of grams, yet utilizing actual numbers of atoms, molecules, or ions would also be unclear. To fill this gap between extremely small and extremely huge numbers, scientists created the mole.
A mole is precisely 6.02214076 × 10^23, which is the number of particles defined by Avogadro. For all intents and purposes, the mass of one mole of a substance in grams and the mass of one molecule in daltons are essentially equivalent.
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on mixing chalk powder and water ,a mixture is obtained. give any four reason to support the fact that mixture so obtained is a suspension .
On mixing chalk powder and water, the mixture obtained is suspension.
The four reasons to support the fact that the mixture of chalk and water is suspension are:-
The dissolved chalk will settle down after some time, hence the chalk is unstable.The particles of chalk can be clearly visible to the eye.The mixture of chalk and water is a heterogenous mixture because the composition is non-uniform and the chalk particles can be separated by filtration.The mixture can scatter the beam of light passing through it.Therefore, the above mixture is a suspension as it has all the qualities of a suspension.To learn more about suspension, visit: https://brainly.com/question/17650174
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Which of the following was NOT a position for a member of the WAC?
A. Pilot
B. Infantry
C. Radio Operator
Answer:
B
Explanation:
It is really easy to be honest
Pilot was NOT a position for a member of the Women's Army Corps (WAC). Option A is correct.
During World War II, the Women's Army Corps was the women's branch of United States Army. Women served in various roles within the WAC, but being a pilot was not one of the positions available to them.
Women were not assigned to pilot positions in the WAC. The United States Army Air Forces (USAAF) had its own separate organization, the Women Airforce Service Pilots (WASP), which recruited civilian women pilots to serve in non-combat roles, ferrying aircraft and performing other flight-related duties. The WASP was not part of the WAC.
Infantry: The role of infantry, which involves direct ground combat, was restricted to male soldiers during World War II. Women in the WAC were not assigned to infantry positions. Instead, they served in a wide range of support roles, such as clerical work, administration, logistics, communication, medical services, and more.
Radio Operator: Women in the WAC did serve as radio operators. Radio communication was a vital component of military operations, and women played important roles in operating and maintaining communication systems. They received training in radio operations and were assigned to various units where their skills were utilized.
Hence, A. is the correct option.
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Would the lack of blood vessels likely pose more of a survival problem for the simple or stratified epithelial? Why ?
The lack of blood vessels does not pose a survival problem for the simple or stratified epithelial because they (epithelial tissues) are weakly irrigated by blood vessels.
What are epithelial tissues?Epithelial tissues are a specialized type of tissue that cover the surfaces (both internal and external surfaces) of the body and organs, which do not contain many blood vessels conversely to connective tissues.
In conclusion, the lack of blood vessels does not pose a survival problem for the simple or stratified epithelial because they (epithelial tissues) are weakly irrigated by blood vessels.
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