The limiting reactant is O2.
To determine the limiting reactant, we need to compare the number of moles of each reactant present.
First, we convert the given masses of phosphorus and oxygen to moles:
25.0 g of P4 = 25.0 g / (123.8 g/mol) = 0.202 mol
50.0 g of O2 = 50.0 g / (32.00 g/mol) = 1.5625 mol
Next, we use the balanced equation for the reaction to determine the stoichiometry of each reactant:
P4 + 5O2 → P4O10
From the equation, we can see that for every one mole of P4, 5 moles of O2 are required.
We can then compare the number of moles of each reactant present:
0.202 mol P4 / 1 mol P4 = 0.202
1.5625 mol O2 / 5 mol O2 = 0.3125
We can see that the number of moles of O2 is less than the number of moles of P4 required by the reaction, so the limiting reactant is O2.
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Tooth enamel, or hydroxyapatite, is an essential part of the tooth structure. Its composition is 39. 8% calcium,
18. 5% phosphorous, 41. 43% oxygen, and 2% hydrogen. What is the empirical formula? It has a molar mass of
1004 g/mol. What is the molecular formula of this compound?
The empirical formula of this compound is Ca3(PO4)2.
What is an Empirical formula?
An empirical formula is a type of chemical formula that shows the simplest ratio of atoms in a molecule, rather than the total number of atoms. It is the simplest possible chemical formula that shows the relative numbers of each type of atom in a molecule.
The molecular formula is Ca3(PO4)2•H2O, which indicates that the compound is composed of three calcium atoms, two phosphate atoms, and two water molecules. The molar mass of this compound is 1004 g/mol, which is two times the molar mass of the empirical formula (502 g/mol). Therefore, the molecular formula of this compound is Ca3(PO4)2•H2O.
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When atoms of aluminum-27 are bombarded with alpha particles, a neutron and an element are produced. The particular isotope formed is
An alpha particle bombardment of aluminum with an atomic number of 27 results in the production of a neutron and phosphorus 15. The particular isotope formed is aluminum-28.
Fundamental alterations take place at the level of the atomic nucleus during nuclear reactions. Analyze the properties of the neutron, which has a mass similar to that of a proton but no electric charge. As a result, when it interacts with the aluminum core, the atomic number should remain constant but the atomic mass should rise by one unit. The newly produced atom is in an excited state when it transitions to the base state with the emission of a high-energy radiation called a gamma ray. Aluminum-28 isotope is formed. ⁷A₂₇ + ⁰n₁ → ⁷Al₂₈ˣ
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18) Write the expression: the sum of the quantity h and 2 divided by 4. A) h 4 2 B) h 2 4 C) h 2 4 D) 4 h 2
The expression is [tex]\frac{(h+2)}{4}[/tex] which can be solved by BODMAS rule
The abbreviation BODMAS, which stands for "Brackets, Order of powers or roots, Division, and Multiplication," is followed by the BODMAS rule. A stands for addition and S for subtraction. According to the BODMAS rule, multi-step mathematical statements must be solved in the BODMAS order from left to right. Similar to how Addition and Subtraction depend on which comes first in the sentence, Division and Multiplication are thought of as interchangeable operations.
The expression can be written as follows WE have 2 quantities h and 2
Their sum can be written as h+2 Now We have the sum divided by 4 so it can be written as : [tex]\frac{(h+2)}{4}[/tex]
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If 1.0 mole of methane reacts with oxygen to produce carbon dioxide and water, what mass of water is produced?
44 grams
16 grams
36 grams
18 grams
Answer:
36 grams
Explanation:
What volume of oxygen is needed to completely react with 171.9 g of S8 at STP?
S8(s) +1202(g) →8S03(1)
All chan
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, the volume of oxygen needed to completely react with 171.9 g of S8 at STP is 180.09L.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
S[tex]_8[/tex](s) +12O[tex]_2[/tex](g) →8SO[tex]_3[/tex](l)
171.9 g of S8
mole of S[tex]_8[/tex]= 171.9 g/ 256.52g/mol
=0.67mol
The mole of oxygen = 12×0.67
= 8.04mol
volume of oxygen= 22.4× 8.04
=180.09L
Therefore, the volume of oxygen needed to completely react with 171.9 g of S8 at STP is 180.09L.
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Why do animals and plants have different habitats?
Answer:
Why do animals and plants have different habitats?
This is because the planet has different climates and different environments in every continents, organisms have evolved and adapted to these factors, that is why they have different habitats as well.
It is safe to say that organisms and their environment really are interrelated and needs each other in order to survive and continue.
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Compare and contrast the carbon cycle of 1500 and of 2021
Answer:
Carbon moves from the atmosphere to the land, ocean, and life through biological, chemical, geological and physical processes in a cycle called the carbon cycle. Because some carbon gases are greenhouse gases, changes in the carbon cycle that put more carbon in the atmosphere also warm Earth’s climate.
What are the missing coefficients for the skeleton equation below? Cr(s)+Fe(NO3)2(aq)>Fe(s)+Cr(NO3)3(aq)
Answer:
2 Cr(s) + 3 Fe(NO3)2(aq) = 3 Fe(s) + 2 Cr(NO3)3(aq)
Explanation:
I balanced this chemical equation so that both sides are equal, meaning that the mass of reactants is equal to mass of products.
How many liters of. 225 M Na2S solution would be required to react completely with 81. 8 g Fe(C2H3O2)3? (The molar mass of iron (III) acetate is 233. 00 g/mol. )
0.002 liters of 225 M Na2S solution is required to completely react with 81.8 g Fe(C2H3O2)3
Starting from the balanced equation of the reaction and the molar mass of iron (III) acetate (Fe(C2H3O2)3, first the reacting moles of this compound are determined, then the amount of reacting moles of sodium sulfide (Na2S) is determined and finally the amount of solution that contains said amount of moles.
Balanced equation of the reaction3Na2S + 2Fe(C2H3O2)3 → 6NaC2H3O2 + Fe2S3
Determination of liters of 225 M Na2S solution for a complete reactionThis determination is made in three steps:
Determination of reactant moles of Fe(C2H3O2)3Determination of the reactant moles of Na2SDetermination of the volume of solution with the number of reacting moles of Na2SDetermination of reactant moles of Fe(C2H3O2)3If 233.00 g of Fe(C2H3O2)3 is equivalent to 1 mol of Fe(C2H3O2)3
So 81. 8 g Fe(C2H3O2)3 equals x mol of Fe(C2H3O2)3
X mol of Fe(C2H3O2)3 = 81. 8 g Fe(C2H3O2)3 x 1 mol of Fe(C2H3O2)3 / 233.00 g of Fe(C2H3O2)3
X mol of Fe(C2H3O2)3 = 0.351 mol
Determination of the reactant moles of Na2SIf 2 moles of Fe(C2H3O2)3 react with 3 moles of Na2S
Then 0.351 mol of Fe(C2H3O2)3 reacts with x mol of Na2S
X mol of Na2S = 0.351 mol Fe(C2H3O2)3 x 3 mol of Na2S / 2 mol of Fe(C2H3O2)3 = 0.526 mol
Determination of the volume of solution with the number of reacting moles of Na2SIf there are 225 moles of Na2S in 1 liter of solution
So there are 0.526 moles of Na2S in x liter of solution.
X liter of solution = 0.526 mol of Na2S x 1 liter of solution / 225 mol of Na2S = 0.0023 liters, that is, 2.3 ml
Therefore, 0.0023 liters of 225M Na2S solution is required.
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A team of scientists claim that they have discovered a new experimental
method for determining atomic mass. Which of the following is necessary for
the claim to be considered valid?
A. The atomic mass of an element according to the new method
must be greater than its previous measurement.
B. The method must work for all isotopes.
C. The atomic mass of an element according to the new method
must be less than its previous measurement.
OD. Another team of scientists must be able to replicate the results of
the experiment.
SUBMIT
For a team of scientists to claim that they have discovered a new experimental method for determining atomic mass, their claim is to be considered valid only if another team of scientists is able to replicate the results of the experiment.
In order for a scientific claim to be considered valid, it is important that the results of the experiment can be replicated by other researchers.
Replication means that other scientists should be able to obtain the same results using the same methods. This helps to ensure that the results are accurate and reliable, rather than being a fluke or an error.
Without the ability to replicate the results, it is difficult to have confidence in the validity of the claim, as it may be due to uncontrolled variables or other factors that cannot be reproduced. Ensuring that results are replicable is an important part of the scientific process and helps to build a strong foundation of knowledge.
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The reaction of hydrogen (H2) and fluorine (F2) produces hydrofluoric acid (HF). How many grams of HF are produced if 3. 00 g of hydrogen react with excess fluorine with a 25 percent yield?
1.50g of hydrofluoric acid is produced if 3.00 g of hydrogen reacts with excess fluorine with a 25 percent yield.
The balanced equation for the reaction of hydrogen (H2) and fluorine (F2) to form hydrofluoric acid (HF) is:
H2 + F2 -> 2HF
To calculate the amount of HF produced, we'll use the concept of theoretical yield and percent yield.
The theoretical yield is the maximum amount of product that can be formed based on the amount of reactants used.
Here, we're given that 3.00 g of hydrogen is used, so to find the theoretical yield of HF, we'll use the molar ratio of hydrogen to hydrofluoric acid in the balanced equation.
1 mol of H2 produces 2 mol of HF
So, 3.00 g of H2 produces 2*3.00g = 6.00g of HF
Percent yield is the ratio of the actual yield to the theoretical yield multiplied by 100%.
It's given that the yield is 25%.
So the actual yield of hydrofluoric acid will be:
Actual yield = (Theoretical yield) x (percent yield/100)
Actual yield = 6.00g x (25/100)
Actual yield = 1.50g
So, 1.50g of hydrofluoric acid is produced if 3.00 g of hydrogen reacts with excess fluorine with a 25 percent yield.
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Step 1: treatment with NaBH_4 Add curved arrows for the first step, Treat Na^+ as a spectator ion. Step 2: treatment with D_2O Add curved arrows for the second step. Do not show Na^+ counter ion.
The reaction occurs via a nucleophilic substitution mechanism. The D_2O molecule acts as the nucleophile, attacking the carbon atom of the CH_3CH_2OBH_3 molecule.
Step 1:
NaBH_4 + CH_3CH_2OH → CH_3CH_2OBH_3 + NaOH
Step 2:
CH_3CH_2OBH_3 + D_2O → CH_3CH_2OD + BH_3OH
Step by explanation in detail
Step 1:
NaBH_4 + CH_3CH_2OH → CH_3CH_2OBH_3 + NaOH
The reaction occurs via a nucleophilic substitution mechanism. The Na^+ cation acts as a spectator ion and does not take part in the reaction. The BH_4- anion acts as the nucleophile, attacking the carbon atom of the CH_3CH_2OH molecule. This causes the C-O bond to break and the BH_3 group to form a bond with the carbon atom. This results in the formation of the CH_3CH_2OBH_3 molecule and the NaOH molecule.
Step 2:
CH_3CH_2OBH_3 + D_2O → CH_3CH_2OD + BH_3OH
The reaction occurs via a nucleophilic substitution mechanism. The D_2O molecule acts as the nucleophile, attacking the carbon atom of the CH_3CH_2OBH_3 molecule. This causes the C-B bond to break and the D atom to form a bond with the carbon atom. This results in the formation of the CH_3CH_2OD molecule and the BH_3OH molecule.
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Time Remaining 4 hours 45 minutes 24 seconds04:45:24 Check my workCheck My Work button is now disabledItem 15 Time Remaining 4 hours 45 minutes 24 seconds04:45:24 Protactinium-234 has a half-life of 1 minute. How much of a 400. g sample protactinium would remain after 4 minutes
After 4 minutes, 400 g of the sample would have decayed to 400 g - (200 g x 4) = 396.2 g.
What is protactinium?Protactinium (symbol Pa) is a rare, radioactive, metallic element in the actinide series of the periodic table. It has an atomic number of 91 and an atomic mass of 231. It is found in trace amounts in nature, but can be artificially produced in a nuclear reactor. Protactinium is a soft, silvery-gray metal that is soluble in acids and insoluble in bases. It has a high melting point and is moderately toxic. It has a variety of uses, including as a fuel source in nuclear reactors and in medical research.
After 4 minutes, 400 g of protactinium-234 would have decayed to approximately 396.2 g.
This is because the half-life of protactinium-234 is 1 minute, meaning that in one minute, half of the original amount (200 g) of the sample will decay.
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What is the freezing point of the solution after you add an additional 1. 34 g (Use i = 2. 5 for MgCl2)
The freezing point of the solution after you add an additional 1.34 g is -0.808°C.
What is freezing point of a solution?A solution's freezing point is lower than the pure solvent's freezing point. This means that for freezing to happen, a solution needs to be cooled to a lower temperature than the pure solvent.
We use the equation: to determine the mass of the solution
Density = mass/volume
1.05 g/ml = mass/ 50ml
mass = 1.05×50
mass = 52.5g.
Percentage of magnesium chloride in the solution is 1.52%
Mass of magnesium chloride in the solution = 1.52 % of 52.5 g
Mass of magnesium chloride in the solution = 1.52/100×52.5
Mass of magnesium chloride in the solution = 0.798g
The following equation is used to determine depression in freezing point:
ΔTf = Freezing point of pure solution - Freezing point of solution
ΔTf = i Kf m
Freezing point of pure solution - Freezing point of solution = i Kf m
m = m solute × 100/M solute × W solvent
Given values,
Freezing point of pure solution (water) is 0°C
i is Vant hoff factor = 2.5
Kf molal freezing point elevation constant = 1.86°C/m
m solute given mass of solute (magnesium chloride) = [0.798 + 1.34] g
m solute = 2.138 g
M solute molar mass of solute (magnesium chloride) = 95.2 g/mol
W solvent mass of solvent (water) = [52.5 - 0.798] g = 51.702 g
substitute the given values,
0 - Freezing point of solution = 1×1.86×2.138×1000/95.2×51.702
Freezing point of solution = -0.808°C.
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Complete question is " A 50 mL solution is initially 1.52% MgCl₂ by mass and has a density of 1.05 g/ml
What is the freezing point of the solution after you add an additional 1.34 g MgCl₂? (Use i = 2.5 for MgCl₂)."
A vessel is filled with a gas at a temperature of 30 degree celsius and operator of 67cm mercury calculate the final pressure of the volume of the gas is doubled it is heated to 80degree celcious
The final pressure is 6312.935 Pa.
The final pressure of the gas can be calculated using the Ideal Gas Law, PV = nRT.
In this situation, the volume of the gas is doubled and the temperature is increased from 30 degrees Celsius to 80 degrees Celsius, while the number of moles of gas and the ideal gas constant remains constant.
Therefore, the pressure of the gas will decrease as the volume doubles and the temperature increases. The final pressure can be calculated by multiplying the initial pressure by the ratio of the initial volume to the final volume and the ratio of the final temperature to the initial temperature.
Final pressure = (Initial pressure) x (Initial volume / Final volume) x (Final temperature / Initial temperature)
The initial pressure is 67cm mercury. 1cm mercury = 133.322 Pa so 67cm mercury = 67*133.322 =8933.294 Pa.
The final temperature is 80-degree celsius = 80+273 = 353K
The final pressure =8933.294 x (1/2) x (353/303) = 6312.935 Pa
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Calculate the maximum amount of picric acid (in grams) that can be obtained if 0.552mL of phenol (density
It is critical to develop a PheDH with specificity and high activity since it is crucial for the manufacture of chiral pharmacological intermediates and the detection of phenylketonuria.
Here, a PheDH gene, pdh, was discovered that encodes a novel BhPheDH with 61.0% similarity to the previously identified PheDH from Microbacterium sp. In comparison to the PheDH from Nocardia sp., the BhPheDH demonstrated superior stability in hot environments (40–70°C) and optimal activity at 60°C and pH 7.0. Additionally, sodium salt has the potential to greatly boost both its activity and thermostability. The residual activity of the BhPheDH was found to be 1.8-fold higher than that of the control group following incubation for 2 hours in 3 M NaCl at 60 °C (without NaCl).
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True or false? 1.0 grams of oxygen (O) has the same number of atoms as 1.0 gram of silver (Ag).
Answer:
true hope it helps
Explanation:
have a nice day
How many moles is 20 grams?
0.5 moles are present in 20 grams of calcium.
The mole, which is denoted by the symbol "mol," is the volume of a system that includes as many elementary particles as there are atoms in 0.012 kilograms of carbon 12.
The number of atoms, molecules, or ions that make up one mole of a substance is 6.022 × 10²³ . The term "Avogadro's number" or "Avogadro's constant" refers to the number 6.022 × 10²³
Atomic Mass of Calcium = 40u
(Atomic Mass is same as Molar Mass, so)
Molar Mass of Calcium = 40g
Formula to find number of moles
Number of Moles = given mass / molar mass
= 20 / 40 = 0.5 moles
Therefore, 0.5 moles are present in 20 grams of calcium.
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The complete question is
How many moles are there in 20 g of calcium
what are the chemical changes that occur when making ice cream in a bag?
Answer:
When making ice cream, you're using physical changes. When you shake your bag, you're freezing the milk, which means the water in it is turning from a liquid (water) into a solid (ice).
What is an irony definition?
In literary classes, the three most popular types are verbal irony, dramatic irony, and situational irony. When a speaker or narrator says something that contradicts what they mean, what they intend, or what the context necessitates, this is called verbal irony.
What is irony?One thing is expressed while another is meant in an ironic statement. For example, on a chilly, wet gray day, you would exclaim, "What a gorgeous day!" Alternatively, if you were suffering from a severe case of food sickness, you may respond, "Wow, I feel terrific today." "ffers points of view and ideas that are, at most, intriguing... However, it does not reach the truth." Ronagh and Souder are particularly concerned with scientific assertions that are not meant to be taken seriously.
Here,
The three most common varieties in literary studies are verbal irony, dramatic irony, and situational irony. Verbal irony occurs when a speaker or narrator says something that contradicts what they mean, what they intend, or what the context requires.
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describe a method to investigate how the temperature changes when different masses of ammonium
Answer:
Decrease temperature with increase in ammonium nitrate concentration.
Explanation:
The temperature changes when different masses of ammonium nitrate are dissolved in water because the ammonium nitrate takes energy from the surrounding water environment for the breaking of ionic bonds as a result the temperature of water decreases. When more concentration of ammonium nitrate is added to water, more decrease occur in temperature of water and the water becomes cold.
Show all your work and make sure to label all the numbers with the correct units if you do, I will give you brainly:
A: A sample of sulfuric acid has a mass of 15.0 g. How many molecules are in this sample?
B: How many moles of sulfuric acid are present in 45 g of this sample?
C: How much would a .750 mole sample of Ammonium sulfate weigh?
D: What is the mass percent of hydrogen in this sample?
A sample of gas at 15 atmospheres and 445 K is cooled to 250 K. What pressure will the gas be under after it is cooled? Round to the nearest hundredth.
A. 26.7 atm
B. 25 atm
C. 8.43 atm
D. 10 atm
Answer:
Explanation: 8.43
Orange juice has a pH of 4. What is its relative acidity compared to pure water, which has a pH of 7
The relative acidity of orange juice compared to pure water is 1000times. The relationship between acid strength and pH is inverse.
A scale that historically denoted "potential of hydrogen" was used to describe how basic or acidic an aqueous solution was. The pH values of acidic solutions are typically lower than those of basic or alkaline solutions. The pH scale can be used to gauge how strong an acid is. Higher pH values result in weaker acids, while lower pH values result in stronger acids. Therefore, we may conclude that the relationship between acid strength and pH is inverse.
Given the pH of orange juice = 4
Then concentration of orange juice (M1) = 10^-4M
pH of pure water = 7
The concentration of [H+] in water (M2) = 10^-7M
The relative pH = 10^-4/10^-7 = 10^3
Hence its relative acidity compared to pure water is 1000 times.
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You start with two reactants. One reactant has a mass of 13.6 grams and the other reactant has a mass of 72.9 grams. 22 grams of gas are released during the reaction. What is the total mass of all of the products formed in this reaction?
Answer:
64.5g
Explanation:
First you add the mass of reactant 1 and reactant 2, then you simply subtract the amount of gas released from your answer, and that would be the total mass of ALL the products formed.
My work:
13.6g + 72.9 = 86.5g
86.5g - 22g = 64.5g
Why is the mass of one mole of carbon (C) less than the mass of one mole Oxygen (O), even though the number of atoms of each element is the same
Chemistry quizzes What is the mass of a single carbon atom if a mole of carbon atoms weighs 12 grams. The fact that 1 mole of carbon atoms weighs 12 grams is a given.
There are 6. 022 10 23 atoms in total, or Avogadro's number, in a mole of carbon atoms. As a result, 1 carbon atom weighs 2 10 - 23 g (in grams). The weight of one mole of carbon atoms is 12 g. 12 g to 12 amu. Because we defined the mole to make it so, the atomic mass and molar mass are in agreement. A material can have a variable mass per mole while yet having the same number of particles. Are there any examples you might use to support the claim? In current usage, the term "mole" merely denotes a group of countable items, more specifically the Avogadro number of the entities in question.
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A dash of vinegar and baking soda balloon system weighed 65 grams. After releasing the carbon dioxide, the system weighed 63.5 grams. How many grams of carbon dioxide were produced?
Answer:
1.5 grams of carbon dioxide
Explanation:
According to this question, a dash of vinegar and baking soda balloon system weighed 65 grams. The system weighted 63.5grams after releasing the carbon dioxide in it.
This means that, to get the amount of carbon dioxide (CO2) produced in the system, we subtract the mass of the system after releasing CO2 from the initial mass of the system before releasing CO2.
That is;
Mass of CO2 produced = 65g - 63.5g
Mass of CO2 produced = 1.5grams
Which of the following is always equal to the number of protons in an atom 1pc
of a given element?
Mass number
Olonic number
O Atomic number
Answer:
[tex]\huge\mathfrak\purple{answer..} \\ \\ \huge\mathfrak\green{atomic \: number} \\ \\ \huge\mathfrak\red{hope \: it \: helps...}[/tex]
For each of the following chemical equations, write all possible mole ratios. a. 2HgO(s) → 2Hg(l ) + O2(g) b. 4NH3(g) + 6NO(g) → 5N2(g) + 6H2O(l ) c. 2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3H2(g)
What is c. 2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3H2(g)
a) The mole ratio is 2/1
b) The mole ratio is 4/6
c) The mole ratio is 2/3
What is the mole ratio?We have to note that the mole ratio is the ratio of the stoichiometric coefficient that we have between two reactants that can be found in an equation. In the case of the reaction equations that we have, we must look closely at each equation.
As we can see, each of the reaction equations is balanced and we can now be able to obtain the mole ratio of each of the reaction as shown in the answer above.
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how do you solve a stoichiometry?
Answer:
Explanation:
Although stochiometry is very scary loking math it is very easy and and fun to learn.
First Balance the chemical equation (Meaning there are equal amounts of elements at end and begining
Second Convert your units to mols
mols are what allows for stochiometry math to work to know how to find the mols takes practice and knowing when to write the math.
Then from there is just knowing how to go from grams to kg or g to mg and etc