The energy change when the temperature of 0.950 kg of water decreased from 103 °C to 60.5 °C is 2308.87 kJ.
What is the heat energy change when the temperature of 0.950 kg of water decreased from 103 °C to 60.5 °C?The heat energy change when the temperature of 0.950 kg of water decreased from 103 °C to 60.5 °C is determined from the formulas below:
Heat change 1 = Heat capacity as gas * moles * temperature change
Heat change 2 = Heat of vaporization, ΔHvap * moles
Heat change 3 = Heat capacity as liquid, Cp (l) * moles * temperature change
moles of water = 950 kg * 1000 g/kg * 1 mol/ 18g = 52.78 mole
Heat change 1 = 33.6 * 52.78 * (103 - 100) = 5320.224 J
Heat change 2 = 40.67 * 1000 * 52.78 = 2146562.6 J
Heat change 3 = 75.3 * 52.78 * (100 - 60.5) = 156986.193 J
Total heat change = 5320.224 J + 2146562.6 J + 156986.193 J
Total heat change = 2308869.017 J = 2308.87 kJ
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In a lab experiment, 7.97 g of phosphorus reacts with bromine to form 69.65 g of phosphorus tribromide. How much phosphorus tribromide would be formed if 12.05 g of phosphorus reacted with 61.68 g of bromine? answer:______gi put what i got in the image and it is wrong sorry
1) List the known and unknown quantities.
First experiment:
Reactants
Phosphorus: 7.97 g.
Bromine: excess.
Product
Phosphorus tribromide: 69.65 g.
Second experiment
Reactants
Phosphorus: 12.05 g.
Bromine: 61.68 g.
Product
Phosphorus tribromide: unknown.
2) Write and balance the chemical equation.
[tex]2P+3Br_2\rightarrow2PBr_3[/tex]3) Convert the masses.
3.1-Convert the mass of P to moles of P.
The molar mass of P is 30.97 g/mol.
[tex]mol\text{ }P=12.05\text{ }g\text{ }P*\frac{1\text{ }mol\text{ }P}{30.97\text{ }g\text{ }P}=0.38909\text{ }mol\text{ }P[/tex]3.2-Convert the mass of Br to moles of Br.
The molar mass of Br2 is 159.8080 g/mol.
[tex]mol\text{ }Br_2=61.68\text{ }g\text{ }Br_2*\frac{1\text{ }mol\text{ }Br_2}{159.8080\text{ }g\text{ }Br_2}=0.38596\text{ }mol\text{ }Br_2[/tex]4) Which is the limiting reactant?
4.1-How many moles of Br2 do we need to use all of the P?
The molar ratio between Br2 and P is 3 mol Br2: 2 mol P.
[tex]mol\text{ }Br_2=0.38909\text{ }mol\text{ }P*\frac{3\text{ }mol\text{ }Br_2}{2\text{ }mol\text{ }P}=0.583635\text{ }mol\text{ }Br_2[/tex]We need 0.583635 mol Br2 and we have 0.38596 mol Br2. We do not have enough Br2. This is the limiting reactant.
4.2-How many moles of P do we need to use all of the Br2?
The molar ratio between Br2 and P is 3 mol Br2: 2 mol P.
[tex]mol\text{ }P=0.38596\text{ }mol\text{ }Br_2*\frac{2\text{ }mol\text{ }P}{3\text{ }mol\text{ }Br_2}=0.25731\text{ }mol\text{ }P[/tex]We need 0.25731 mol P and we have 0.38909 mol P. We have enough P. This is the excess reactant.
5) Moles of phosphorus tribromide produced from the limiting reactant.
Limiting reactant: 0.38596 mol Br2.
The molar ratio between Br2 and PBr3 is 3 mol Br2: 2 mol PBr2.
[tex]mol\text{ }PBr_2=0.38596\text{ }mol\text{ }Br_2*\frac{2\text{ }mol\text{ }PBr_3}{3\text{ }mol\text{ }Br_2}=0.25731\text{ }mol\text{ }PBr_3[/tex]6) Conver the moles of Pbr3 to mass of PBr3.
The molar mass of PBr3 is 270.6858 g/mol.
[tex]g\text{ }PBr_3=0.25731\text{ }PBr_3*\frac{270.6858\text{ }g\text{ }PBr_3}{1\text{ }mol\text{ }PBr_3}=69.6502\text{ }g\text{ }PBr_3[/tex]The mass of PBr3 produced in the reaction is 69.65 g PBr3.
.
This question is to the Brainly employees: Can you please make it to where it doesn't cover the answer because you have to pay for it. Please and thank you sir or mam.
Answer:
right
Explanation:
How many moles of solute are present in 250 mL of 4.00 M HCI?
Answer:
Answer. There are 0.1 moles of solute in 250 mL of 0.4 M solution.
What is neutralization reaction? Use an example to describe the components of neutralization reaction
1) Neutralization reaction.
In this type of reaction an acid and a base react to form a salt and water. In the course of the reaction H+ and OH- are produced. Afterward, they combine to produce water.
2) Example.
Acid: HCl
Base: NaOH
Salt: NaCl
[tex]\text{HCl}+\text{NaOH}\rightarrow NaCl+H_2O[/tex]Why does an atom want to form an octet or duet?And yes I know these rules and I know that it “wants” a stable electronic configuration and a filled shell.
Answer
An atom wants to form an octet or duet because an atom always wants to be in the most stable form. For any atom, stability is achieved by following the octet rule or duet rule, which is to say all atoms (with a few exceptions) want 8 electrons (octet) or 2 electrons (duet) in their outermost electron shell just like noble gases.
The phenolic indicator (ln-OH) has approximately the same pKa as a carboxylic acid. Which H is the most acidic proton in ln-OH? Circle or otherwise indicate the most acidic proton. Explain why that H is the most acidic proton in ln-OH (i.e. what makes its conjugate base well stabilized)?
The most acidic hydrogen atom is the hydrogen atom that have been bonded to the oxygen atom.
What is an acidic proton?
We say that a proton is an acidic proton if the proton is able to leave very easily from the rest of the compound. We know that there are several factors that could make a proton that is found in a molecule to become a labile or an acidic proton. The acidity of a proton largely stem from the fact that electron density between the hydrogen atom and the atom to which it is bonded is weak. As such, the bond is weakened by the lengthening of the bond and a consequent lability of the attached hydrogen atom as discussed here.
In the compounds as shown, the most acidic proton is the proton that is attached to the oxygen atom. This is because, the extensive conjugation in the molecule withdraws electrons from the 0-H bond and this makes the hydrogen atom to become labile or acidic.
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what is the molar mass of anhydrous solid, mol
what is the molar mass of anhydrous solid, mol?
Help I am not sure how to do this number 8
Answer: The temperature of the gas sample under the conditions given is 30.313 K
Explanation:
The question requires us to determine the temperature, in Kelvins, of a C2H6 gas sample with the following mass, volume and pressure:
mass of C2H6 = m = 561.51g
volume of gas = V = 47.048L
pressure of gas = P = 100.03 kPa
To solve this problem, we can apply the equation of ideal gases rearranged to calculate the temperature, as shown below:
[tex]PV=nRT\rightarrow T=\frac{PV}{nR}[/tex]where T is the temperature we want to calculate, P corresponds to the pressure of the gas, V is its volume, n is its number of moles and R is the constant of gases (8.314 kPa.L/mol.K).
Note that the only valye that was not provided by the question was the number of moles. We can determine the number of moles n considering the mass of the sample given (561.51g) and the molar mass of the gas C2H6, which we can determine from the atomic masses of C and H.
The atomic masses of C and H are 12.011 and 1.0078 amu, thus we can calculate the molar mass of C2H6 as:
[tex]molar\text{ mass \lparen C}_2H_6)=2\times12.011+6\times1.0078=30.069g/mol[/tex]Now that we know the mass of the gas sample (561.51 g) and the molar mas of the gas (30.069 g/mol), we can determine the number of moles of gas as it follows:
[tex]\begin{gathered} number\text{ of moles = }\frac{mass\text{ \lparen g\rparen}}{molar\text{ mass \lparen g/mol\rparen}}\rightarrow n=\frac{m}{M} \\ \\ n=\frac{561.51g}{30.069g/mol}=18.674mol \end{gathered}[/tex]Therefore, the number of moles of C2H6 gas that we need to consider is 18.674 moles.
Next, we can apply the equation of ideal gases to calculate the temperature of the gas:
[tex]\begin{gathered} T=\frac{PV}{nR} \\ \\ T=\frac{(100.03kPa)\times(47.048L)}{(18.674mol)\times(8.314kPa.L/mol.K)}=30.313K \end{gathered}[/tex]Therefore, the temperature of the gas sample under the conditions given is 30.313 K.
What is TRUE about expert witnesses?
A.
They offer personal and professional knowledge.
B.
They are not allowed to practice their testimony.
C.
They are required to link all evidence to the crime.
D.
They have all written a book about their area of expertise.
The true statement about is expert witnesses that they are required to link all evidence to the crime.
So, option C is correct.
Who are expert witnesses?An expert witness is described particularly in common law countries such as the United Kingdom, Australia, and the United States, is a person whose opinion by virtue of education, training, certification, skills or experience, is accepted by the judge as an expert.
Expert witnesses are required or expected to to link all evidence to the crime.
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I need help to this problem
The energy efficiency of this rotating space heater is equal to: C. 64%.
What is energy efficiency?Energy efficiency can bed defined as a process that involves the use of less energy to provide goods and services or perform the same task. This ultimately implies that, energy efficiency helps to reduce air pollution and degradation of the environment.
How to determine the efficiency of this space heater?Mathematically, energy efficiency can be calculated by using this formula:
Energy efficiency = WO/WI × 100
Where:
WO represents the output energy.WI represents the input energy.Note: the amount of energy that was used to produced thermal energy represents the output energy used for heating the room.
Substituting the given parameters into the formula, we have;
Energy efficiency = 896/1,400 × 100
Energy efficiency = 0.64 × 100
Energy efficiency = 64%.
In this context, we can reasonably infer and logically deduce that the space heater's efficiency is equal to 64 percent.
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Complete Question:
A rotating space heater used 1,400 joules of energy while heating a room. Of that total, 896 joules produced thermal energy, 181 joules produced kinetic energy, 203 joules produced light energy, and 120 joules produced sound energy. What is the space heater's efficiency?
O 156.25%
O 36%
O 64%
O 56.25%
Sulfur burns in oxygen to form sulfur dioxide. Write a skeleton equation for this chemical reaction.
A skeletal chemical equation is a representation of a chemical reaction using chemical formulae of reactants and products.
Sulfur = S
Oxygen = O
Sulfur dioxide = SO2
The skeleton equation is:
[tex]S+O_2\text{ }\Rightarrow SO_2[/tex]Here the skeleton equation = balanced equation.
strategies for controlling carbon monoxide are in conflict with strategies for controlling oxides of nitrogen .
Answer:
I do not know how to answer this question. Is it even a question?
Explanation:
A gas is confined to a cylinder under constant atmospheric pressure,. When the gas undergoes a particular chemical reaction , it releases 135 kJ of heat to its surroundings and does 63 KJ of P-V Work on its surroundings. What are the values of ∆H and ∆E for this process ?
Answer:
[tex]\begin{gathered} \triangle H=-135kJ \\ \triangle E=-198kJ \end{gathered}[/tex]Explanations:
From the question, we are given the following
Amount of heat released to the surroundings = 135kJ
Work done to its surroundings q = 63 kJ
The derivation of the enthalpy at constant pressure is expressed as;
[tex]\triangle H=\triangle U+\triangle(P_{int}V)[/tex]where;
[tex]\begin{gathered} \triangle U\text{ is the internal energy} \\ P_{int_{}}\text{ is the internal pressure} \\ V\text{ is the volume of the gas} \end{gathered}[/tex]Since the cylinder gas is under constant pressure, then the enthalpy will be equal to the work done to have:
[tex]\triangle H=q[/tex]Since q = 63kJ, hence;
[tex]\triangle H=q=-135kJ[/tex]Next is to calculate the change in the change in the internal energy
Using the law of energy conservation which states that the change in internal energy is equal to the heat transferred to, less the work done by, the system. Mathematically;
[tex]\begin{gathered} \triangle E=q+W \\ \triangle E=-135kJ+(-63kJ) \\ \triangle E=-198kJ \end{gathered}[/tex]Hence the change in internal energy for the process is -198kJ
In a different titration, a solid sample containing some Fe2+ ion weighs 1.705g. It requires 36.44 mL, 0.0244 M KMnO4 to titrate the Fe2+ in the dissolved sample to a pink end point.
a. How many moles MnO4 ion are required?
b. How many moles Fe2+ are there in the sample
c. How many grams of Fe are there in the sample?
d. What is the percent Fe in the sample?
The accurate responses are;
a) Number of moles of permanganate ion = 8.89 * 10^-4 moles
b) Number of moles of iron = 4.4 * 10^-3 moles
c) Mass of iron in the sample = 0.25 g
d) Percentage of iron in the sample = 14.7 %
What is titration?The term titration refers to the kind of reaction in which the amount of substance can be obtained by the accurate determination of the volumes of the substances that have reacted in the process.
a) The number of moles of the permanganate ion that are involved is obtained from;
36.44 /1000 L * 0.0244 M = 8.89 * 10^-4 moles
b) Given that the reaction is 1:5 in the mole ratio of the permanganate ion and the iron III ion
1 mole of permanganate reacts with 5 moles of iron II
8.89 * 10^-4 moles reacts with 8.89 * 10^-4 moles* 5 moles/ 1 mole
= 4.4 * 10^-3 moles
c) Mass of the iron II ion in the sample = 4.4 * 10^-3 moles * 56 g/mol = 0.25 g
d) Percent of the iron in the sample = 0.25 g/1.705g * 100/1
= 14.7 %
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10. What is the Arrhenious definition for acids and bases? Why do we use thisdefinition?
ANSWER
Definition of an acid; is a substance that produced hydrogen ions (H+) as the only positive ion when dissolved in water or in an aqueous solution. it increases the concentration of hydrogen ions in an aqueous solution.
Definition of the base; are hydroxide compounds that give hydroxide ion (OH-) on dissociation in water. it increases the concentration of hydroxide ions in an aqueous solution.
Why do we use the definition: it helps us to understand the acid-base properties of substances in an aqueous medium. neutralization, hydrolysis, and strength of acids and bases
EXPLANATION:
Arrhenius defined acid and base in the following way
According to Arrhenius, he defined an acid as a substance that produced hydrogen ions (H+) as the only positive ion when dissolved in water or in an aqueous solution. it increases the concentration of hydrogen ions in an aqueous solution.
[tex]\begin{gathered} \text{According to Arrhenius} \\ HA_{(aq)}\rightleftarrows H^{+_{}}_{(aq)}+A^-_{(aq)} \end{gathered}[/tex]Bases are hydroxide compounds that give hydroxide ion (OH-) on dissociation in water. it increases the concentration of hydroxide ions in an aqueous solution.
[tex]\text{BOH}_{(aq)}\rightleftarrows B^+_{(aq)}+OH^-_{(aq)}[/tex]Arrhenius's definition of acid and base is still in use because it helps us to understand the acid-base properties of substances in an aqueous medium. neutralization, hydrolysis, and strength of acids and bases
Suppose 2.68 g of barium acetate is dissolved in 300. mL of a 45.0 m M aqueous solution of ammonium sulfa
Calculate the final molarity of acetate anion in the solution. You can assume the volume of the solution doesn't
acetate is dissolved in it.
Round your answer to 3 significant digits.
The term "total moles of a solute contained in a kilogram of a solvent" is used to describe molality. Molal concentration is another name for molality. It is a measurement of a solution's solute concentration.
What is the molarity unit?Molarity is a unit of measurement for the concentration of a material in a specific volume of solution (M). The amount of a solute in one liter of solution is known as its molarity. The molarity of a solution is sometimes referred to as its molar concentration.
As a result, we start by assuming that the reaction is finished and that its volume is constant.
The following is the balanced stoichiometric equation:
BaSO4 + 2NH4(CH3COO) = Ba(CH3COO)2 + (NH4)2SO4.
First, we must identify the surplus reactant and the one that the process has entirely consumed.
For Ba(CH3COO)2,
The formula for moles is (Mass/) (Molar Mass)
Mass of barium acetate is 2.68 g.
Molar mass of barium acetate is 255.43 g/mol.
There are 0.0104 moles, or (2.68/255.43), in total.
Number of moles for (NH4)2SO4 = (Concentration in mol/L) (Volume in L)
Ammonium surface concentration in mol/L is 45 M.
(300/1000) x volume in L = 0.3 L
45 divided by 0.3 to equal 13.5 moles.
According to the reaction's stoichiometric balance, 1 mole of Ba(CH3COO)2 produces 1 mole of (NH4)2SO4.
Ba(CH3COO)2 produces 2 moles of NH4(CH3COO) from 1 mole.
Ba(CH3COO)2 will provide 2 0.0591 moles of NH4(CH3COO), or 0.1182 moles of NH4(CH3COO), from 0.0591 moles of Ba(CH3COO)2.
If NH4(CH3COO) has a molarity, give the number of moles. Volume in L
0.1182 moles are the number of moles.
0.3 L is equal to L of the solution.
NH4(CH3COO) has a molarity of (0.01182/0.3) = 0.0394 M.
Consider that 0.0394 M of NH4(CH3COO) likewise contains 0.0394 M of acetate ion because 1 mole of NH4(CH3COO) includes 1 mole of acetate ion.
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The local police department just bought a Reflected Ultraviolet Imaging System (RUVIS) device. What is MOST likely the purpose of this purchase?
A.
to test DNA from blood in their lab
B.
to individualize hair samples
C.
to determine if blood is human or animal
D.
to find and process more fingerprints
Answer:
To find a process more fingerprints (A uv imaging is used to capture and detect substances such as sweat which prints on a surface)
What is TRUE about expert witnesses?
A.
They offer personal and professional knowledge.
B.
They are not allowed to practice their testimony.
C.
They are required to link all evidence to the crime.
D.
They have all written a book about their area of expertise.
The statement they offer personal and professional knowledge is TRUE about expert witnesses (Option A).
What is the role performed by witnesses?The specific role performed by witnesses in a given case is to answer questions associated with a subject matter, which are associated with evidence to confirm or reject a given hypothesis.
Therefore, with this data, we can see that the work performed by witnesses is to provide answers in a given subject matter, which is information that may be used as empirical evidence to confirm or reject a given process.
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Which process is not reversible?Dissolving sugar in water Burning butane in a candle lighterMelting waxExtracting iron metal from iron (III) oxide
Answer
The process that is NOT reversible is Burning butane in a candle lighter
Explanation
All other processes can be reversed
A reaction between liquid reactants takes place at 28.0 degree celcuis in a sealed, evacuated vessel with a measured volume of 15.0L. Measurements show that the reaction produced 10.0g of dinitrogen difluoride gas.
Calculate the pressure of dinitrogen difluoride gas in the reaction vessel after the reaction. You may ignore the volume of the liquid reactants. Round your answer to 2 significant digits.
The pressure of N2F2 will be 1.64 atm.
Given data:
Mass of N2F2 = 66 grams
Molar mass of N2F2 = 66 g/mol
Temperature = 28°C = 273 +28 = 301 Kelvin
volume = 15 L.
Gas constant = 0.08206 L*atm/K* mol
Number of moles can be determined by using the formula:
Number of moles = mass of N2F2 / Molar mass of N2F2
Number of moles = 66 g/ 66 g/mol = 1 moles.
Volume can be determined by using the formula:
P*V = n×R×T
where, P is pressure, V is volume, T is temperature.
P = (n×R×T)/ V
P = 1 * 0.08206 * 301 )/15 = 1.6466 atm.
The pressure of the sulfur tetrafluoride gas is 1.64 atm.
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Which subatomic particle is positively charged?ProtonNeutronElectronNone
Explanation:
A proton is a positively charged subatomic particle.
A neutron is a neutrally charged subatomic particle.
An electron is a negatively charged subatomic particle.
Answer:
The first option is correct.
The half-life of phosphorus−33 is 25.0 days. How much of a 2.7−oz sample of phosphorus−33 will remain after 150 days?
If phosphorus-33 have an half-life of 25 days the amount of phosphorus-33 that will remain after 150 days is 0.042 oz.
What is half-life?Half-life is the time taken for half the sample of a radioactive substance to decay.
To calculate the amount of phosphorus-33 that will remain after 150 days, we use the formula below.
Formula:
R' = R/[tex]2^{T/t}[/tex]........ Equation 1Where:
R = Original amount of phosphorus-33R' = Amount of phosphorus-33 that will remain after 150 daysT = Total timet = half-lifeFrom the question,
Given:
R = 2.7 ozT = 150 dayst = 25 daysSubstitute these values into equation 1
R' = 2.7/([tex]2^{150/25[/tex])R' = 2.7/[tex]2^{6}[/tex]R' = 2.7/64R' = 0.042 ozHence the amount of phosphorus-33 that will remain after 150 days is 0.042 oz.
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How much water needs to be added to a 8.6317 M NaCl solution to obtain a 1.0421 M solution, if you start with 4.7869 liters of solution?
The amount of water needed to be added to a 8.6317 M NaCl solution to obtain a 1.0421 M solution starting with 4.7869 liters of solution would be 34.8629 L.
DilutionThe problem here has to do with dilution. The dilution principle states that the number of moles of solute in a solution is constant before and after dilution.
In other words, the dilution principle can be mathematically expressed as:
[tex]m_1v_1[/tex] = [tex]m_2v_2[/tex].
Where [tex]m_1[/tex] and [tex]m_2[/tex] are molarities before and after dilution; [tex]v_1[/tex] and [tex]v_2[/tex] are volumes before and after dilution.
In this case: [tex]m_1[/tex] = 8.6317 M, [tex]m_2[/tex]= 1.0421 M, [tex]v_1[/tex]= 4.7869 L. We are to determine v2.
[tex]v_2[/tex] = [tex]m_1v_1[/tex]/ [tex]m_2[/tex]
= 8.6317x4.7869/1.0421
= 39.6498 L
If the final volume of the solution is 39.6498 L and the starting volume is 4.7869, then the amount of water needed can be calculated as:
39.6498 - 4.7869 = 34.8629 L
Thus, the amount of water that will be added to the original solution in order to arrive at the diluted solution is 34.8629 L.
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How many molecules of carbon dioxide, CO2, comprise 1.22 moles?
How many molecules of carbon dioxide, CO₂, comprise 1.22 moles?
According to Avogadro's Number we have 6.02 * 10^23 molecules in one mol of molecules. So:
1 mol of CO₂ = 6.02 * 10^23 molecules of CO₂
Then:
1.22 moles of CO₂ * 6.02 * 10^23 molecules of CO₂ / 1 mol of CO₂ = 7.34 * 10^23 molecules of CO₂
There are 7.34 * 10^23 molecules of CO₂ in 1.22 moles of it
Which hydrogen below will have the greatest partial positive charge?Group of answer choicesHIHClHBrHFcannot determine
The hydrogen bonded to the most electronegative element will have the greatest partial positive charge. This is because electronegativity corresponds to the ability of the nucleus of an atom to attract the electrons involved in a chemical bond.
So the more electronegative, the more partial negative charge the atom will have.
Linus Pauling created a scale of the most electronegative elements, which can be of help in determining the intensity of polarization of different bonds:
F > O > N > C > Br > I > S > C > P > H
In this case, F is the most electronegative element.
So hydrogen will have the greatest partial positive charge bonded to F.
Answer: HF
What is the balanced, net ionic equation for the reaction described below?Aqueous sodium phosphate and aqueous iron (III) chloride react to produce aqueous sodium chloride and solid iron (III) phosphate.
A net ionic equation is the one that only includes the ions that are involved in the formation of the solid.
According to the information the solid formed is iron (III) phosphate, and the ions involved are Fe3+ and PO43-.
It means that the net ionic equation is:
[tex]Fe_{(aq)}^{3+}+PO_{4(aq)}^{3-}\rightarrow FePO_{4(s)}[/tex]The correct answer is the second choice.
Calcium like to lose how many electron/s to form an ion?Group of answer choices123cannot determine
Answer: the best option to answer the question is the second one (or letter B), "2"
Explanation:
The question requires us to identify how many electrons a calcium (Ca) atom would lose to form an ion.
We can analyze the electron configuration of Ca to understand how many electrons it would lose.
The atomic number of Ca is 20, thus its electron configuration is as it follows:
[tex]1s^2\text{ 2}s^2\text{ 2}p^6\text{ 3}s^2\text{ 3}p^6\text{ 4}s^2[/tex]From the electron configuration, we can see that Ca presents 2 electrons in its valence shell (4s2). To achieve stability, it is easier for Ca to lose these two electrons and form a Ca2+ ion.
Therefore, the best option to answer the question is the second one (or letter B), "2".
Which of the following behaves most like an ideal gas at the conditions indicated?
A H2(g) molecules at 10-3 atm and 200°C
B O2(g) molecules at 20 atm and 200°C
The gas that behaves most like an ideal gas at the conditions indicated is H2(g) molecules at 10-3 atm and 200°C
What is ideal behavior?Recall that a gas is said to show an ideal behavior when the pressure of thee gas is low and the temperature of the gas is high. Recall that, at a high temperature and a low pressure, the interaction that exists between the molecules of the gas is decreased as such the molecules of the gas would tend to move faster.
We can see that the hydrogen gas has a lower pressure at the same temperature hence the interaction that is know to exists between the molecules of the gas is minimal.
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4 Al(s) + 302(g)->2Al2O3(s)When 42.39 g of Al and 85.16 g of O2 were reacted, 6.67 grams of aluminum oxidewere obtained. What is the percent yield? (Hint: You need to determine which one isthe limiting reactant and then the theoretical yield).
The reaction presented to us is balanced since we have 4 aluminum atoms and 6 oxygen atoms on both sides of the reaction.
Now, we have a given mass of aluminum and oxygen, we must first determine the moles of each using their molar mass.
Moles of Al
[tex]\begin{gathered} \text{Mol of Al}=GivengAl\times\frac{1molAl}{MolarMass,gAl} \\ \text{Mol of Al}=42.39gAl\times\frac{1molAl}{26.98gAl}=1.57molAl \end{gathered}[/tex]Moles of O2
[tex]\begin{gathered} MolO_2=GivengO_2\times\frac{1molO_2}{MolarMass,gO_2} \\ MolO_2=85.16gO_2\times\frac{1molO_2}{31.998gO_2}=2.66molO_2 \end{gathered}[/tex]Now that we have the number of moles, we will calculate what the limiting reagent is, that is, the reagent that limits the reaction by its number of moles.
To find the limiting reactant we must compare the amount of product obtained with the given amount of reactant separately. The reactant that produces the least amount of product is the limiting reactant.
Using Al as limiting reactant
[tex]\begin{gathered} \text{MolAl}_2O_3=MolAl\times\frac{2molAl_2O_3}{4molAl} \\ \text{MolAl}_2O_3=1.57molAl\times\frac{2molAl_2O_3}{4molAl}=0.785molAl_2O_3 \end{gathered}[/tex]Using O2 as a limiting reactant
[tex]\begin{gathered} \text{MolAl}_2O_3=MolO_2\times\frac{2molAl_2O_3}{3molO_2} \\ \text{MolAl}_2O_3=2.66molO_2\times\frac{2molAl_2O_3}{3molO_2}=1.77molAl_2O_3 \end{gathered}[/tex]Aluminum is the reagent that produces the least amount of aluminum oxide, so the limiting reagent will be Al. And it will produce 0.785 moles of Al2O3. In grams this will be:
[tex]\text{gAl}_2O_3=0.75molAl_2O_3\times\frac{101.95gAl_2O_3}{1molAl_2O_3}=80.03gAl_2O_3[/tex]The percent yield will be:
[tex]\begin{gathered} \text{Percent yield=}\frac{\text{Actual yield}}{Theoretical\text{ yield}}\times100\% \\ \text{Percent yield=}\frac{\text{6}.67gA_{}l_2O_3}{80.03ggA_{}l_2O_3}\times100\%=8.33\% \end{gathered}[/tex]The percent yield will be 8.33%
What happens when you cover burning candles with different size glass containers?
Answer:
eventually, they'll always stop burning - how long that takes depends on the glass size
Explanation:
the candle stops burning once it consumes all the oxygen inside the glass. the bigger the glass, the more oxygen there is, but eventually, even that will run out. so, smaller glass means faster, larger slower.
hope that helps