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
Choose two of the following scientists: Anton Lavoisier, John Dalton, JJ Thomson, Robert Millikan, Ernest Rutherford, James Chad
elixir [45]

Answer:

John Dalton:

John Dalton was the scientist who introduced atomic theory in the field of chemistry. Dalton worked on different gases and formulated this theory. The main points of Dalton's theory are:

  • Every element present is made up of atoms.
  • Atoms of an elements are have the same same properties whereas these properties are different for each element.
  • According to his theory, an atom could not be broken down.
  • Different atoms combine or get separated from each other during a chemical reaction.

Ernest Rutherford:

Ernest Rutherford is known as the father of nuclear physics due to his impressing research work on radioactivity of atoms. Rutherford was the first scientist to discover the nucleus of an atom and prove that the nucleus was charged. He also described that the electrons circle around the nucleus of an atom.

6 0
3 years ago
What is 0.151 g in scientific notation
Ahat [919]

Answer: Scientific notation- 1.51 x 10^{-1}

Explanation: I got this by moving the decimal, so that there is one non-zero digit to the left of that decimal point. Tip- The number of decimal places you move will be the exponent on the 10.

Moved right- Negative

Moved left- Positive

4 0
2 years ago
Read 2 more answers
What is the correct name for the compound CaSO4•2H2O?
zlopas [31]
CaSO4.2H2O is a white crystal at room temperature. It is soluble in water. Gypsum can be used as a fertilizer.


This Might Be The Answer Idk?
5 0
3 years ago
The formation of covalent bonds is...
Evgen [1.6K]
A covalent compound is made when two or more nonmetal atoms bond by sharing valence electrons. The shared valence electrons between two nonmetal atoms is called a covalent bond. Covalent bonds are formed when two atoms begin sharing electrons.
4 0
3 years ago
Pls help me on this question????
astraxan [27]

Explanation:

The first one is series circuit as it is joined one after another while the second one is parallel circuit joined in a parallel way. Ok the line just like this --------- is the wire , the sign like this | | is the battery and the circles with cross are the bulbs

Hope this helps :) Have a great day

7 0
3 years ago
Other questions:
  • Which one of the following is a common acid? A. Antacid
    8·2 answers
  • The resulting atomic number of an element that emits 1 alpha particle, 1 positron, and 3 beta particles is
    7·1 answer
  • False answer it's F**** wrong
    11·1 answer
  • Form the complementary solution to the homogeneous equation. yc(t) = Cl [ ] +C2 Construct the (simplest) particular olution of t
    10·1 answer
  • Dome mountains are formed when:
    7·1 answer
  • A mixture of gases at a total pressure of 95 kPa contains nitrogen, carbon dioxide and oxygen. The partial pressure of carbon di
    5·2 answers
  • Which of these is an example of sexual reproduction, involving meiosis?
    11·2 answers
  • Check out this long-form version of the periodic table. It shows where the two rows of
    15·1 answer
  • A mass of 2.20 kg of sodium phosphate is converted number of moles
    9·1 answer
  • How many moles are in 8.25×10²⁵ molecules of water(H20)?​
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!