Answer:
3.97 x 10²² molecules
Explanation:
To find the moles, you need to use the Ideal Gas Law:
PV = nRT
In this equation,
-----> P = pressure (atm)
-----> V = volume (L)
-----> n = moles
-----> R = Ideal Gas constant (0.08206 atm*L/mol*K)
-----> T = temperature (K)
Before you can plug the values into the equation, you need to (1) convert the pressure from torr to atm (by dividing by 760), then (2) convert the volume from mL to L (by dividing by 1000), and then (3) convert the temperature from Celsius to Kelvin (by adding 273).
P = 800.0 torr / 760 = 1.05 atm R = 0.08206 atm*L/mol*K
V = 1500 mL / 1000 = 1.5 L T = 19.0 °C + 273 = 292 K
n = ? moles
PV = nRT
(1.05 atm)(1.5 L) = n(0.08206 atm*L/mol*K)(292 K)
1.579 = n(23.96)
0.0659 = moles
Now, you need to convert moles to molecules using Avogadro's Number.
Avogadro's Number:
6.022 x 10²³ molecules = 1 mole
0.0659 moles 6.022 x 10²³ molecules
------------------------ x ------------------------------------- = 3.97 x 10²² molecules
1 mole
An 80 ev electron impinges upon a potential barrier 100 ev high and 0. 2 nm thick. what is the probability the electron will tunnel through the barrier?
In the above question the probability the electron will tunnel through the barrier is 0.011%.
What do you mean by electron volt?An electron volt is the amount of energy required to move a charge equal to 1e⁻ across a potential difference of 1eV.
To calculate the probability the electron will tunnel through the barrier is calculated as -
Energy of electron
E=80eV
=80×1.6×10⁻¹⁹
=128×10⁻¹⁹
Height of the barrier U=100 eV
=100×1.6×10⁻¹⁹J
Thickness L=0.2×10⁻⁹m
Probability T=e⁻²cl
C=√2m(U-E)/h
=√[2×1.67×10⁻²⁷(160-128)×10⁻¹⁹] / 1.055×10⁻³⁴
=10.34×10⁻²³/1.055×10⁻³⁴
=9.8×10¹¹
2CL=2×9.8×10¹¹×0.2×10⁻⁹
=3.92×10²
T=e⁻²cl
= 1/e⁻³⁹²/¹⁰⁰⁰⁰
=0.0198%
=0.011%
Hence ,the probability the electron will tunnel through the barrier is 0.011%.
Learn more about electron volt ,here:
https://brainly.com/question/17136195
#SPJ4
When the forecast calls for freezing rain, salt is often spread on the roads. Why is this done?
Chemists can use moles to calculate:
A. How much of the products are needed and how much reactant will be made.
B. How much of the reactants are needed and how much product will be made.
C. How much of the reactants are needed, but not how much product will be made.
D. How much product will be made, but not how much of the reactants are needed.
Please Help!!!
[tex] \qquad \qquad \bf \huge\star \: \: \large{ \underline{Answer} } \huge \: \: \star[/tex]
B. How much of the reactants are needed and how much product will be made.
Chemists use mole in calculations to calculate the amount of product that will be formed when certain known amount of reactants are used at the end of reaction.
The moles are used to determine the atoms and molecules in a substance. It is used by chemists to determine the amount of reactants needed and products produced. Thus, option B is correct.
What are moles?A mole is said to be defined as the estimation of the small entities like the atoms as that of the Avagadro's number 6.022 × 10²³. It defines the number of particles contained in a substance.
The moles of the substances are determined by the mass of the substance and its molar mass. The moles are given as,
Moles = mass ÷ molar mass
The moles give the estimation of the amount of the reactants needed to produce the products in a chemical reaction.
Therefore, option B. the moles tell the amount of the reactants required to produce the product.
Learn more about moles here:
https://brainly.com/question/16188500
#SPJ2
What is the mass of a 32.5-ml sample of ethanol? the density of ethanol is 0.789 g/ml.
Answer:
25.6 grams of ethanol in 32.5 ml of the substance.
Explanation:
The density of ethanol can be used as a conversion factor. We know that:
Ethanol is 0.789 g/ml. That becomes a conversion factor that we may write as (0.789 g/ml) and then convert either grams ethaanol or ml ethanol into the other unit. We are given volume of ethanol: 32.5 ml.
Note that when we multiply (0.789 g/ml) by (32.5 ml) the ml unit cancels, leaving just grams. That's what we want, so:
(0.789 g/ml)(32.5 ml) = 25.6 grams of ethanol in 32.5 ml of the substance.
If a person wearing such a mask exhales 0. 65g of CO2 every minute. Calculate the number of grams of O2 that will be produced in 15 minutes.
If a person wearing such a mask exhales 0. 65g of [tex]CO_{2}[/tex] every minute then the number of grams of [tex]O_{2}[/tex] that will be produced in 15 minutes is 7.09 grams .
Calculation ,
Since number of moles of carbon dioxide exhale is equal to the number of moles of oxygen produce ,
Mass of carbon dioxide exhale per minute = 0.65 g
Mass of carbon dioxide exhale 15 minute = 0.65 g × 15 = 9.75 g
Number of moles of carbon dioxide = given mass / molar mass = 9.75 g/44
Number of moles of carbon dioxide = 0.221 moles
Number of moles of oxygen = 0.221 moles = given mass / molar mass
Number of moles of oxygen = 0.221 moles = given mass / 32
Mass of oxygen = 0.221 moles × 32 = 7.09 grams
To learn more about number and grams
https://brainly.com/question/482478
#SPJ4
What is the ph of a 0. 10 m solution of NaCN at 25°C?(ka= 4. 9 x 10^-10for hcn at 25°C. )
The pH of a a 0. 10 m solution of NaCN at 25°C is 11.15
Calculation
The reaction in the solution is given below
[tex]CN^{-} + H_{2} O[/tex] → HCN + [tex]OH^{-}[/tex]
initial 0.1
change ( -x) (+x)
equilibrium ( 0.1 - x ) x
Kb = [HCN] [[tex]CN^{-}[/tex] ]/[[tex]CN^{-}[/tex] ]
Kb × Ka = Kw = 1.0 × [tex]10^{-14}[/tex]
Kb = 1.0 × [tex]10^{-14}[/tex] / 4.9 × [tex]10^{-10}[/tex] = [HCN] [[tex]CN^{-}[/tex] ]/[[tex]CN^{-}[/tex] ] = [tex]x^{2}[/tex]/ ( 0.1 - x )
Kb = 2.04× [tex]10^{-5}[/tex] = [tex]x^{2}[/tex]/ ( 0.1 - x )
Since , [NaCN] /Kb > 100 , we can simplify the above equation to
= 2.04× [tex]10^{-5}[/tex] = [tex]x^{2}[/tex]/ ( 0.1 )
x = 1.43 × [tex]10^{-3}[/tex] M = [HCN] = [ [tex]OH^{-}[/tex]]
Then pOH = 2.84
pH + pOH = 14
pH = 14- pOH = 14 - 2.84 = 11.15
Therefore , the pH is 11.15
learn about pH and solution
https://brainly.com/question/11300720
#SPJ4
An aqueous solution has a molality of 3. 64 kcl. what is the the mass percent of kcl in the solution? enter your answer to three significant figures and in units of mass percent
The mass percentage of KCl solution is 21.34%
Calculation,
Given molality of KCl aqueous solution = 3. 64 m = 3. 64 mole/ Kg
It means 3. 64 mole of solute present in 1Kg of solvent
or , 3. 64 mole of solute present in 1000 g of solvent ( water )
Mass of solute ( KCl ) = 3. 64 mole×74.55 g/mole =271.3 g
The total mass of solution ( KCl + water ) = 271.3 g + 1000 g = 1271.3 g
Mass percentage is equal to percentage of mass of solute present in total mass of solution.
Mass percentage = 100×271.3 g/1271.3 g = 21.34%
to learn more about mass percentage
https://brainly.com/question/27108588
#SPJ4
What is the rate of a reaction if the value of kis 3 and [A] and [B] are each 2
M?
Rate = K[A]²[B]
OA. 12 (mol/L)/s
OB. 24 (mol/L)/s
OC. 2 (mol/L)/s
о D. 36 (mol/L)/s
The rate of reaction of the value of KIS 3 and [A] and [B] are each 2M is: 24 (mol/L)/s (Option B)
What is rate of reaction?
In chemistry, the rate of reaction describes how quickly a chemical reaction develops.
It is frequently described in terms of either the concentration of a reactant that is spent in a unit of time or the concentration of a product that is generated in a unit of time (amount per unit volume).
What is the calculation that supports that above answer?
Recall that the rate equation is:
Rate = K[A]²[B]
Hence:
Concentration of A = 2M
Concentration of B = 2M
K = 3
Taking the values and substituting them, we have:
Rate = 3 (mol/L)⁻³/s×[2]² ×[2]
Rate = 24 (mol/L)⁻³/s
The rate of reaction can be used as a valuable diagnostic tool. We may devise strategies to increase production by learning how quickly things are created and what slows down reactions.
This knowledge is necessary for the industrial production of various chemicals, such as:
fertilizersmedications, and home cleaners.Learn more about rate of reaction:
https://brainly.com/question/24795637
#SPJ1
Please help me understand this!
Answer:
It's too short. Write at least 20 characters to explain it well.
Explanation:
It's too short. Write at least 20 characters to explain it well.
Octanol is slightly soluble in water, and water is very soluble in octanol. why is it important to presaturate octanol with water and water with octanol when measuring ow?
N-Octanol and water are chosen because the connection between a substance's hydrophilicity and lipophilicity is measured by [tex]K_{OW}[/tex] (n-Octanol/Water partition coefficient). When a chemical is more dissolves in fat-like solvents like n-octanol, the value is more significant than one, when it's more dissolved in water, the value is lower.
What is the partition coefficient?
The partition coefficient for the two-phase network comprising n-octanol and water is known as the [tex]K_{OW}[/tex] value. N-Octanol-Water Partition Ratio is another name for it.The connection between a substance's hydrophilicity (its ability to dissolve in water) and lipophilicity (its ability to dissolve in fat) is measured by [tex]K_{OW}[/tex]. The value is bigger if a drug is more accessible in fat-like liquids like n-octanol and less if a compound seems more water-soluble.Owing to linkage or fragmentation, substances that are involved in the octanol-water combination as multiple synthetic entities are each given a unique [tex]K_{OW}[/tex] ratio.So, N-Octanol is chosen because it has a carbon/oxygen ratio that is comparable to that of lipids and because it shows both hydrophobic and hydrophilic properties. N-octanol, therefore, resembles the makeup and characteristics of cells and other living things.
Learn more about octanol here:
https://brainly.com/question/7768749
#SPJ4
Extra was made by mixing different components together but it appears to have only one phase which term best describes categorizes make sure a
Solution is the term which best describes mixture A which was made by mixing different components together but has only one phase.
What is solution?Any mixture of one or more solutes that have been dissolved in a solvent is referred to as a solution.To create a homogenous mixture, a solute must dissolve in a solvent.The material known as a solute dissolves in a solvent to form a homogenous mixture.The material that is present in the highest concentration is called a solvent.A true solution won't spin apart in a centrifuge.It has a uniform distribution of particles.Example of homogenous mixture is the solution of salt and water.Learn more about solution here:
https://brainly.com/question/13812915
#SPJ4
25. 22 the reaction of phenylmagnesium bromide with methyl benzoate followed by acidification produces triphenylcarbinol. what are the sources of phenyl groups in triphenylcarbinol?
Triphenylcarbinol( or triphenylmethanol) gets its phenyl groups from phenylmagnesium bromide.
Synthesis of triphenylcarbinol:
A typical laboratory experiment for demonstrating the Grignard reaction is the synthesis of triphenylmethanol using methyl benzoate, benzophenone, and phenylmagnesium bromide. Diethyl carbonate is a possible starting material.
Characteristics:
An organic substance is a triphenylmethanol. It is a white, crystalline substance that dissolves well in alcohol, diethyl ether, and benzene but not in water or petroleum ether. Due to the creation of a persistent "trityl" carbocation, it generates a bright yellow hue in very acidic solutions. Important dyes include several triphenylmethanol derivatives.Triphenylmethanol has a core tetrahedral carbon atom, three phenyls (Ph) rings, and an alcohol group attached to it. With lengths of around 1.47Å for all three C-Ph bonds and 1.42Å for the C-O link, these connections are characteristic of sp3-sp2 carbon-carbon bonds.Three neighboring phenyl groups give off specific qualities that are reflected in the alcohol's reactivity.Learn more about triphenylmethanol here:
https://brainly.com/question/15089315
#SPJ4
A cylinder was charged with 1.25 atm of oxygen gas, 6.73 atm of argon, and 0.895 atm of xenon. What is the mole fraction of each gas
Considering the Dalton's partial pressure, the mole fraction of each gas is:
[tex]x_{oxygen}[/tex]= 0.14[tex]x_{argon}[/tex]= 0.76 [tex]x_{xenon}[/tex]= 0.10Dalton's partial pressureThe pressure exerted by a particular gas in a mixture is known as its partial pressure.
So, Dalton's law states that the total pressure of a gas mixture is equal to the sum of the pressures that each gas would exert if it were alone:
[tex]P_{T} =P_{1} +P_{2} +...+P_{n}[/tex]
where n is the amount of gases in the gas mixture.
This relationship is due to the assumption that there are no attractive forces between the gases.
Dalton's partial pressure law can also be expressed in terms of the mole fraction of the gas in the mixture. The mole fraction is a dimensionless quantity that expresses the ratio of the number of moles of a component to the number of moles of all the components present.
So in a mixture of two or more gases, the partial pressure of gas A can be expressed as:
[tex]P_{A} =x_{A} P_{T}[/tex]
In summary, the total pressure in a mixture of gases is equal to the sum of partial pressures of each gas.
Mole fraction of each gas
In this case, you know that:
[tex]P_{oxygen }[/tex]= 1.25 atm[tex]P_{argon}[/tex]= 6.73 atm[tex]P_{xenon}[/tex]= 0.895 atm[tex]P_{T} =P_{oxygen} +P_{argon}+P_{xenon}[/tex]= 1.25 atm + 6.73 atm + 0.895 atm= 8.875 atmThen:
[tex]P_{oxygen} =x_{oxygen} P_{T}[/tex][tex]P_{argon} =x_{argon} P_{T}[/tex][tex]P_{xenon} =x_{xenon} P_{T}[/tex]Substituting the corresponding values:
1.25 atm= [tex]x_{oxygen}[/tex] 8.875 atm6.73 atm= [tex]x_{argon}[/tex] 8.875 atm0.895 atm= [tex]x_{xenon}[/tex] 8.875 atmSolving:
[tex]x_{oxygen}[/tex]= 1.25 atm÷ 8.875 atm= 0.14[tex]x_{argon}[/tex]= 6.73 atm÷ 8.875 atm= 0.76 [tex]x_{xenon}[/tex]= 0.895 atm÷ 8.875 atm=0.10In summary, the mole fraction of each gas is:
[tex]x_{oxygen}[/tex]= 0.14[tex]x_{argon}[/tex]= 0.76 [tex]x_{xenon}[/tex]= 0.10Learn more about Dalton's partial pressure:
brainly.com/question/14239096
brainly.com/question/25181467
brainly.com/question/14119417
#SPJ1
Al+HCl=AlCl6+H6
is this balanced or unbalanced
Answer:
unbalanced
Explanation:
balanced: Al+HCl=AlCl+H
What are 3 things that make carbon special?
Answer:
1. Carbon is very special because it can form so many compounds
2. Many carbon-based compounds are not attracted to water and so in general do not dissolve in water. As a result, water alone cannot be used to remove grease or oil from a surface, nor will water dissolve our skin, because all of these things are carbon compounds.
3. Carbon can also link together in long chains or rings, carbon to carbon to carbon to carbon and so on.
Explanation:
Sonam has a tank that holds 0.5L of air at a temperature of 300K and a pressure
of 880kPa.
What volume would the air occupy if it were released into the atmosphere, where
the pressure is 102kPa and the temperature is 327K?
Answer:
4.70 L
Explanation:
Use the basic relationship:
P1V1/T1 = P2V2/T2
Re-arrange to:
P1V1 T2 / (T1P2) = V2 To find the new volume
Sub in the values:
880 * .5 * 327 / ( 300*102) = 4.70 L
What would be the molecular formula of a monosaccharide characterized as an aldotetrose?
The molecular formula of a monosaccharide characterized as an aldotetrose is [tex]C_{5}H_{10} O_{5}[/tex].
What is monosaccharide?Any monosaccharide, often known as simple sugar, is one of the fundamental substances that forms the basis of carbohydrates.
Some features of monosaccharide are-
With some more than a hydroxyl group (OH) as well as a carbonyl group (C=O) either in the final carbon atom (aldose) or on the second carbon atom, monosaccharides constitute polyhydroxy aldehydes as well as ketones (ketose). A cyclic molecule is created when one hydroxyl group and the carbonyl group interact in an aqueous solution (hemi-acetal or hemi-ketal). A crystalline, water-soluble monosaccharide is the end product.Dioses, trioses, tetroses, pentoses, hexoses, and heptoses are the different types of monosaccharides according on the quantity of carbon atoms they contain. The majority have five or six.To know more about common monosaccharides, here
https://brainly.com/question/1768793
#SPJ4
What are the spectator ions in the reaction between aqueous zncl2 and aqueous na2co3?(choose all that apply)
Sodium and chloride are the spectator ions in the reaction between aqueous zncl2 and aqueous na2co3.
Spectator ions are ions that are present on both sides of chemical reactions but do not take part in the reaction itself. The spectator ions on both sides of the equation are cancelled in the net chemical reaction. So, to "spectate" is to "see" the other ions in an aqueous solution interact with one another.
An ion known as a spectator is one that is present both before and after a chemical reaction but does not take part in it. Sodium is a spectator ion in an aqueous solution of sodium hypochlorite (NaOCl, bleach): Na+ + HOCl + OH or OCl- + H2O -
Cross out the spectator ions after comparing the reactant and product sides. Observer ions are any dissolved ions that exhibit the same form on both sides.
To learn more about spectator ion please visit -
https://brainly.com/question/22277121
#SPJ4
Calculate the ph at the equivalence point for the titration of 0. 22 m hcn with 0. 22 m naoh. (ka = 4. 9 × 10^–10 for HCN).
The pH at the equivalence point for the titration of 0. 22 m HCN with 0. 22 m NaOH is 11.17
Calculation,
Concentration of NaCN = 0. 22 m/ 2 = 0.11 M ( at equal volumes of acid and base will be used).
The equilibrium is ,
HCN +[tex]H_{2} O[/tex] → [tex]H^{+} + CN^{-}[/tex]
C(1-x) Cx Cx
Where x , is the degree of hydrolysis and
[tex]K_{h}[/tex] = C[tex]x^{2}[/tex]/(1-x)
We know that [tex]K_{h}[/tex] = [tex]K_{w}/K_{a}[/tex] = 1 ×[tex]10^{-14}[/tex]/4. 9 ×[tex]10^{-10}[/tex] = 2.04×[tex]10^{-5}[/tex]
[tex]K_{h}[/tex] = C[tex]x^{2}[/tex] = 2.04×[tex]10^{-5}[/tex] = 0.11 M×[tex]x^{2}[/tex]
[tex]x^{2}[/tex] = 2.04×[tex]10^{-5}[/tex]/0.11 M
x = 1.36×[tex]10^{-2}[/tex]
[tex][OH^{-} ][/tex] = Cx = 1.36×[tex]10^{-2}[/tex] × 0.11 M = 0.15×[tex]10^{-2}[/tex]
[tex][H^{+} ][/tex] = 1 ×[tex]10^{-14}[/tex]/ 0.15×[tex]10^{-2}[/tex] = 6.66×[tex]10^{-12}[/tex]
pH = -㏒[tex][H^{+} ][/tex] = -㏒6.66×[tex]10^{-12}[/tex] = 11.17
The pH at the equivalence point for the titration is 11.17.
To learn more about equivalence point
https://brainly.com/question/14782315
#SPJ4
500. ml of a solution containing 1. 5 m nh4cl(aq) is mixed with 500. ml of a solution containing 0. 50m of naoh(aq). what is the ph of the final solution? (kb(nh3) = 1. 8 x 10-5)
The pH of the solution is determined by the hydrogen ion concentration. The pH of the solution with 1.5 M NH4Cl and 0.50 M NaOH is 8.77.
What is pH?
The potential of the hydrogen ion in the given solution is called pH which determines the acidity and basicity of the solution.
Given
The molar concentration of 500 mL NH4Cl = 1.5 M
The molar concentration of 500 mL NaOH= 0.50 M
Kb (NH3) = 1.8 × 10 -5
First pOH is calculated as,
pOH = pKB + log [NH4Cl][NaOH]
= - log 1.8 × 10-5 + log [1.5][0.50]
= - log 1.8 × 10-5 + log [3]
= 4.744 + 0.477
= 5.221
Now, pH is calculated from pOH as,
pH + pOH = 14
pH = 14 – pOH
= 14 – 5.221
= 8.77
Thus we found that, 8.77 is the pH of the solution with 1.5 M NH4Cl and 0.50 M NaOH.
learn more about pH:
https://brainly.com/question/12942138
#SPJ4
How does the mass per nucleon of an element change as the atomic number increases?
Answer:
Explanation: So, the atomic number is the number of protons present in an atom. For example, Helium's atomic number is 2, meaning it only has 2 protons. In most cases, the number of nuetrons and protons are equal, so Helium (usually) has 2 protons and 2 nuetrons - this is the nucleus. The atomic mass, or mass per nucleon is the proton and nuetron added together, so the atomic mass of Helium is about 4. Therefore, on the periodic table, as the atomic number increases by 1, the atomic mass increases by about 2 (the atomic mass is an average so it's not exact).
If only 0.500 mol of NO2(g) is placed in a 1.0 L container and the reaction is allowed to come to equilibrium, 0.186 mol of N2O4(g) is formed. Find the value of Keq.
Solve using ICE table.
The equilibrium constant of the system is 11.3.
What is the value of Keq?We know that the equilibrium constant shows the extent to which reactants are converted into products.
Now;
2NO2 ⇄ N2O4
[NO2] = 0.500 mol /1 L = 0.500 M
[N2O4] = 0.186 mol /1 L = 0.186 M
The ICE table is;
2NO2 ⇄ N2O4
I 0.5 0
C -2x +x
E 0.5 - 2x 0.186
The concentration of NO2 at equilibrium = 0.5 - 2(0.186) = 0.128
Keq = 0.186/( 0.128)^2
Keq = 11.3
Learn more about equilibrium constant:https://brainly.com/question/10038290
#SPJ1
Find the volume occupied by 22. 0 g of helium gas at 26. 0 ° C and 1. 20 atm of pressure.
The volume occupied by 22. 0 g of helium gas at 26. 0 ° C and 1. 20 atm of pressure is 112.37 L .
Calculation ,
According to ideal gas equation ,
PV = nRT ....(i)
where P is the pressure = 1. 20 atm
V is the volume of the helium gas = ?
R is the universal gas constant = 0.082 atm L /K mol
T is the temperature of the gas = 26. 0 ° C = 299 K
n is the number of moles
Number of miles (n) = given mass/ molar mass =22 g/4 = 5.5 moles
By putting the value of pressure , volume , temperature and universal gas constant in equation ( i) we get
1. 20 atm ×V = 5.5 moles × 0.082×299
V = 5.5 moles × 0.082×299/1. 20 atm = 112.37 L
To learn more about helium gas please click here ,
https://brainly.com/question/13645498
#SPJ4
The density of an unknown gas is 4. 20 grams per liter at 3. 00 atmospheres pressure and 127 °c. what is the molecular weight of this gas?
The molecular weight of this gas will be 45 g/mol .
The state equilibrium equation for a fictitious perfect gas is known as the ideal gas law, sometimes known as the generic gas equation. Although it has significant drawbacks, it represents a decent approximation of the activity of many gases under various conditions.
Ideal gas law can be expressed as:
PV =nRT
Calculation of molecular weight by using ideal as law.
Given data:
P = 3 atm
T = 127 °c
Density = 4. 20 grams per liter
PV =nRT
where p is pressure , T is temperature and R is gas constant.
PV = gram / molecular weight RT
Molecular weight = (g/v)( 1/P) RT
Putting the given data in above equation.
Molecular weight =4.20 × 1/ 3× 400 × 0.0831
Molecular weight = 45 g/mol.
To know more about Molecular weight
https://brainly.com/question/27988184
#SPJ4
How many molecules of propane were in the erlenmeyer flask? Avogadro's number is 6. 022 × 10^23 molecules/mol
3.74×[tex]10^{21}[/tex]
3.74 ×[tex]10^{21}[/tex] molecules of propane were in the erlenmeyer flask.
number of moles of propane can be calculated as moles of propane.
mass of propane = 0.274 g
molar mass of propane = 44.1
So this gives us the value of 6.21×[tex]10^{-3}[/tex] moles of propane
No one mole of propane As a 6.0-2 × [tex]10^{23}[/tex]
so, 6.21 ×[tex]10^{-3}[/tex] × 6. 022 × 10^23
= 3.74 ×[tex]10^{21}[/tex]
Therefore, molecules of propane were in the erlenmeyer flask is found to be 3.74 ×[tex]10^{21}[/tex]
What is erlenmeyer flask?A laboratory flask with a flat bottom, a conical body, and a cylindrical neck is known as an Erlenmeyer flask, sometimes known as a conical flask or a titration flask. It bears the name Emil Erlenmeyer after the German chemist.What purpose does an Erlenmeyer flask serve?Liquids are contained in Erlenmeyer flasks, which are also used for mixing, heating, chilling, incubating, filtering, storing, and other liquid-handling procedures. For titrations and boiling liquids, their sloped sides and small necks make it possible to whirl the contents without worrying about spills.To learn more about calculating total molecules visit:
https://brainly.com/question/8933381
#SPJ4
How many calories (not joules) are given off when 85 gram of steam condenses to liquid water?
45,849 calories are given off when 85 gram of steam condenses to liquid water.
Vaporization is always a highly endothermic (heat-absorbing) process because you must break all the intermolecular interactions present inside of the liquid phase.
So,
Q = mass × heat of vapourization
Q = m×ΔH[tex]_{vap}[/tex]
Q = 85 × 539.4
Q = 45,849 cal
Therefore, 45,849 calories are given off when 85 gram of steam condenses to liquid water.
Learn more about calories here:
https://brainly.com/question/22374134
#SPJ4
2C6H6(g) + 15O2(g) = 12CO2(g) + 6H2O(g)
2.0 moles C6H6 reacts with oxygen according to the reaction above. What volume of water vapor forms at STP?
Taking into account the reaction stoichiometry and STP conditions, Finally, a volume of H₂O of 134.4 L will be formed at STP.
Reaction stoichiometryIn first place, the balanced reaction is:
2 C₆H₆ + 15 O₂ → 12 CO₂ + 6 H₂O
By reaction stoichiometry, the following amounts of moles of each compound participate in the reaction:
C₆H₆: 2 molesO₂: 15 molesCO₂: 12 molesH₂O: 6 molesSTP conditionsStandard pressure and temperature conditions are a set of standard pressure and temperature conditions for laboratory experimental measurements that are established to allow comparisons between different sets of measured data.
Pressure values at 1 atmosphere and temperature at 0 ° C are used and are reference values for gases. And in these conditions 1 mole of any gas occupies an approximate volume of 22.4 liters.
Volume of H₂O formedBy reaction stoichiometry 2 moles of C₆H₆ form 6 moles of water or H₂O.
Now, you can apply the following rule of three: if by definition of STP conditions 1 mole of H₂O occupies a volume of 22.4 liters, 6 moles occupies how much volume?
volume= (6 moles× 22.4 L) ÷ 1 mole
volume= 134.4 L
Finally, 134.4 L of H₂O will be formed.
Learn more about the reaction stoichiometry and STP conditions:
brainly.com/question/28176634
#SPJ1
Mannose (C6H12O6) is a simple sugar found in many fruits and vegetables. How many oxygen atoms are in 7. 15 x 10^23 molecules of mannose?
Number of oxygen atoms present in 7.15×10²³ molecules of mannose are 1.92≈2 a m u .
What is mannose sugar?D-mannose is a simple sugar found in many fruits. It is related to glucose. In some cells it occurs naturally in the body.
Mannose is a six-carbon sugar found in a variety of fruits and vegetables. This sugar is not found free in foods. It is a part of polysaccharide chains attached to a variety of proteins.
To calculate number of oxygen atoms present in 7.15×10²³ molecules of mannose-
Since,
1 molecule of oxygen=2.303×10²³ no. of atoms
Here, total number of molecules of oxygen is 6.
Therefore, 6 molecule of oxygen =6×2.303×10²³÷7.15×10²³
=1.92≈2 a m u .
Hence, the total number of oxygen atoms in 7.15×10²³ molecules of mannose is 1.92 ≈2 a m u.
Learn more about mannose sugar, here:
https://brainly.com/question/7008130
#SPJ4
A substance decays so that the amount a of the substance left at time t is given by: a = a0 ∙ (0.8)t where a0 is the original amount of the substance. what is the half-life (the amount of time that it takes to decay to half the original amount) of this substance rounded to the nearest tenth of a year?
The half-life of the substance is 3.106 years.
What is the formula for exponential decay?The exponential decline, which is a rapid reduction over time, can be calculated with the use of the exponential decay formula. The exponential decay formula is used to determine population decay, half-life, radioactivity decay, and other phenomena. The general form is F(x) = a.Here,
a = the initial amount of substance
1-r is the decay rate
x = time span
The equation is given in its correct form as follows:
a = [tex]a_{0}[/tex]×[tex](0.8)^{t}[/tex]
As this is an exponential decay of a first order reaction, t is an exponent of 0.8.
Now let's figure out the half life. Since the amount left is half of the initial amount at time t, that is when:
a = 0.5 a0
Substituting this into the equation:0.5[tex]a_{0}[/tex] = [tex]a_{0}[/tex]×[tex](0.8)^{t}[/tex]
0.5 = [tex](0.8)^{t}[/tex]
taking log on both sides
t log 0.8 = log 0.5
t = log 0.5/log 0.8
t = 3.106 years
The half-life of the substance is 3.106 years.
To learn more about exponential decay formula visit:
https://brainly.com/question/28172854
#SPJ4
Helium and methane gases are mixed together in a container. what is the ratio of their root-mean-square speeds, i. e. (vrms,helium) / (vrms,methane) ?
Root mean square speed is the estimation of the effect of temperature and weight on kinetic energy. The root means square speed for a mixture of helium and methane is 2. Thus, option d is correct.
What is the root mean square speed?Root mean square speed is the estimation of the square root of the mean value of the squared speeds of the individual gas particles in the mixture.
As it is known that,
Root mean square speed = √{3RT/M}
Where T is constant temperature and R is gas constant. The molecular mass of helium gas is 4 g/mol and of methane is 16 g/mol.
Vrms = √{3RT/M}
For helium, Vrms = √{3RT/4}
And, for methane = Vrms = √{3RT/16}
So, (Vrms,helium) / (Vrms,methane) = 4 / 2 = 2
Therefore, option d. 2 is the root-mean-square speed for the mixture.
Learn more about root-mean-square speeds here:
https://brainly.com/question/13095222
#SPJ4
Your question is incomplete, but most probably your full question was, Helium and methane gases are mixed together in a container. what is the ratio of their root-mean-square speeds, i. e. (Vrms, helium) / (Vrms, methane)?
1/2102cannot tell41/4