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.
Answer:
Explanation: so a combustion occurs when we react a substance with oxygen .you commonly call this "burning'' .therefore combustion will always include oxygen in the equation and the product will include carbon dioxide and give off water vapours
Therefore the general equation for a complete combustion reaction would be
Fuel + O2 ------ CO2 + H2O
Answer:
Explanation:
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In this case, since the molarity of a solution is calculated by diving the moles of solute by the volume of solution in liters, we first compute the moles of barium hydroxide in 35.5 g as shown below:
Then, the liters of solution:
Finally, the molarity turns out:
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In 1770 a Scottish physician and Chemist Daniel Rutherford performed a simple experiment with which he discovered nitrogen. Rutherford being with an empty bottle that he turned upside down in a pan of water so that the air was trapped. A buring candle was placed inside the bottle with the trapped air causing the water to rise a bit. The part of the air that seemed to "disappear" when the candle was bured was oxygen gas and the part of the air that did not "disappear" Ruthford discovered Nitrogen.
