Answer:
Explanation:
Part two of Dalton's theory had to be modified after mass spectrometry experiments demonstrated that atoms of the same element can have different masses because the number of neutrons can vary for different isotopes of the same element. ... Scientists have even developed the technology to see the world on an atomic level!
hoped i helped you :)
<span>6.38x10^-2 moles
First, let's determine how many moles of gas particles are in the two-liter container. The molar volume for 1 mole at 25C and 1 atmosphere is 24.465 liters/mole. So
2 L / 24.465 L/mol = 0.081749438 mol
Now air doesn't just consist of nitrogen. It also has oxygen, carbon dioxide, argon, water vapor, etc. and the total number of moles includes all of those other gasses. So let's multiply by the percentage of nitrogen in the atmosphere which is 78%
0.081749438 mol * 0.78 = 0.063764562 mol.
Rounding to 3 significant figures gives 6.38x10^-2 moles</span>
Answer:
Percent yield = 22.26%
Explanation:
Given data:
Mass of lithium nitride = 105 g
Mass of lithium hydroxide produces = 48 g
Percent yield = ?
Solution:
Chemical equation:
Li₃N + 3H₂O → 3LiOH + NH₃
Number of moles of lithium nitride :
Number of moles = mass/ molar mass
Number of moles = 105 g/ 34.83 g/mol
Number of moles = 3 mol
Now we will compare the moles of lithium nitride with lithium hydroxide.
Li₃N : LiOH
1 : 3
3 : 3×3 = 9 mol
Mass of lithium hydroxide:
Mass = number of moles × molar mass
Mass = 9 mol × 23.95 g/mol
Mass = 215.6 g
Percent yield:
Percent yield = actual yield / theoretical yield × 100
Percent yield = 48 g/ 215.6 g × 100
Percent yield = 22.26%
I think that its a but I'm not sure, sorry if it's wrong