1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Natasha_Volkova [10]
3 years ago
7

A 118-ml flask is evacuated and found to have a mass of 97.129 g. when the flask is filled with 768 torr of helium gas at 35 ?c,

it is found to have a mass of 97.171 g.
Chemistry
1 answer:
Inessa05 [86]3 years ago
7 0
The full question asks to decide whether the gas was a specific gas. That part is missing in your question. You need to decide whether the gas in the flask is pure helium.

To decide it you can find the molar mass of the gas in the flask, using the ideal gas equation pV = nRT, and then compare with the molar mass of the He.

From pV = nRT you can find n, after that using the mass of gass in the flask you use MM = mass/moles.

1) From pV = nRT, n = pV / RT

Data:
V = 118 ml = 0.118 liter
R = 0.082 atm*liter/mol*K
p = 768 torr * 1 atm / 760 torr = 1.0105 atm
T = 35 + 273.15 = 308.15 K

n = 1.015 atm * 0.118 liter / [ 0.082 atm*liter/K*mol  * 308.15K] =0.00472 mol

mass of gas = mass of the fask with the gas - mass of the flasl evacuated = 97.171 g - 97.129 g = 0.042

=> MM =  mass/n = 0.042 / 0.00472 = 8.90 g/mol

Now from a periodic table or a table you get that the molar mass of He is 4g/mol

So the numbers say that this gas is not pure helium , because its molar mass is more than double of the molar mass of helium gas.
You might be interested in
What volume of so2 is produced at 325 k and 1.35 atm when 15.0 grams of hcl reacts with excess k2so3?
Helen [10]
The balanced equation for the above reaction is as follows;
2HCl + K₂SO₃ ---> 2KCl + H₂O + SO₂
stoichiometry of HCl to SO₂ is 2:1
number of moles of HCl reacted - 15.0 g / 36.5 g/mol = 0.411 mol 
according to molar ratio 
number of SO₂ moles formed - 0.411 mol /2 = 0.206 mol
since we know the number of moles we can find volume using ideal gas law equation 
PV = nRT
where
 P - pressure - 1.35 atm x 101 325 Pa/atm = 136 789 Pa 
V - volume 
n - number of moles - 0.206 mol 
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 325 K
substituting values in the equation 

136 789 Pa x V = 0.206 mol x 8.314 Jmol⁻¹K⁻¹ x 325 K 
V = 4.07 L 
volume of SO₂ formed is 4.07 L


8 0
3 years ago
Calculate average kinetic energy of one mole of gas at 517K
Gekata [30.6K]

In an ideal gas, there are no attractive forces between the gas molecules, and there is no rotation or vibration within the molecules. The kinetic energy of the translational motion of an ideal gas depends on its temperature. The formula for the kinetic energy of a gas defines the average kinetic energy per molecule. The kinetic energy is measured in Joules (J), and the temperature is measured in Kelvin (K).

K = average kinetic energy per molecule of gas (J)

kB = Boltzmann's constant ()

T = temperature (k)

Kinetic Energy of Gas Formula Questions:

1) Standard Temperature is defined to be . What is the average translational kinetic energy of a single molecule of an ideal gas at Standard Temperature?

Answer: The average translational kinetic energy of a molecule of an ideal gas can be found using the formula:

The average translational kinetic energy of a single molecule of an ideal gas is  (Joules).

2) One mole (mol) of any substance consists of  molecules (Avogadro's number). What is the translational kinetic energy of  of an ideal gas at ?

Answer: The translational kinetic energy of  of an ideal gas can be found by multiplying the formula for the average translational kinetic energy by the number of molecules in the sample. The number of molecules is  times Avogadro's number:

7 0
3 years ago
How do hydrocarbons differ in structure from carbohydrates.
ICE Princess25 [194]
Hydrocarbons are carbon and hydrogen. Methane is CH4, and propane is C3H8. Methene is CH3, and propene is C3H6. Carbohydrates are hydrates of carbon. They <span>have the general formula (CH2O)x. thats how it differs
</span>
4 0
4 years ago
Almost all of the oxygen on the planet Earth is found in the atmosphere. Is this true or false?
solong [7]
<span>False. Almost all of the oxygen on Earth is found in the oceans.</span>
3 0
4 years ago
Read 2 more answers
In which species does phosphorous have the highest oxidation number?
nignag [31]

the compounds in which phosphorous posses the highest possible oxidation have to mention here.

The species in which phosphorous have the highest oxidation state are: H₃PO₄, P₂O₅, PCl₅

The possible oxidation state of phosphorous is III and V. The highest oxidation state is V. There are several compounds in which phosphorous posses the +5 oxidation state. Like- Phosphoric acid (H₃PO₄), phosphorous pentoxide (P₂O₅), Phosphorous chloride (PCl₅) etc.

The oxidation state of an element depends upon the valence electron the valence shell of phosphorous is 3s² 3p³. Thus there are 5 electrons, as it has vacant 3d orbital thus it can easily form compound having +5 oxidation state.

7 0
3 years ago
Other questions:
  • What is the 10% rule? What is its significance? Why is energy lost?
    7·1 answer
  • Americium-241 is a radioactive substance used in smoke detectors. The half life of americium is 432 years. If a smoke detector i
    14·1 answer
  • Is Consideringual clay different than<br> sedimentary?
    14·1 answer
  • How many moles of sodium chloride (NaCl) solute are in 315 grams of a 91.0 percent by mass solution?
    5·1 answer
  • A 3.301 mass % aqueous solution of potassium hydroxide has a density of 1.05 g/mL. Calculate the molality of the solution. Give
    14·1 answer
  • Plssss help————&gt;An object thats (A. Negatively, B. Neutrally, C. Positively) charged has more electrons than protons. An obje
    13·1 answer
  • A what is matter that is always composed of the same combination of atoms
    15·1 answer
  • a neutral atom is bombarded with sufficient energy that an electron is liberated. the result is called
    14·1 answer
  • How many cl- ions are there in 2. 50 kg of barium chooride.
    14·1 answer
  • Calculate the percent mass of a solution of 5 g NaOH in 95 g of H2O. ​
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!