Answer:
antimony-121 has the highest percent natural abundance
Explanation:
percent natural abundance;
121.76 = 120.90 x + 122.90 (1 - x)
121.76 = 120.90 x + 122.90 - 122.90x
121.76 = -2x + 122.90
121.76 - 122.90 = -2x
x= 121.76 - 122.90/ -2
x= 0.57
Where x and 1 - x refers to the relative abundance of each of the isotopes
Percent natural abundance of antimony-121 = 57 %
Percent natural abundance of antimony-123 = (1 - 0.57) = 43%
Let us remember that isotopy refers to a phenomenon in which atoms of the same element have the same atomic number but different mass numbers. This results from differences in the number of neutrons in atoms of the same element.
We can clearly see that antimony-121 has the highest percent natural abundance.
Answer: c12 has a mass of 12 amu
Explanation:
mass of one mole of c12 = g. So mass of 1 atom of c12 = 1.9927e-23g
This is the only option that correctly describe characterisitics of noble gases.
All noble gases have a unique atomic fingerprint.
All noble gases have valence shells with 8 electrons but Heilum has only 2 valence electrons.
And all noble gases do not easily react with other elements as they have their outermost shell completly filled so they are highly stable.
All noble gases emits different colored light when electrified.
<em>Answer: But Thats Aight</em>
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<em>Explanation: 301</em>
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Answer:
0.2
Explanation:
Given parameters:
Mass of helium = 0.628g
Mass of neon = 11.491g
Mass of argon = 7.613g
Unknown:
Mole fraction of neon = ?
Solution:
The mole fraction of an element is the number of moles of that element to the total number of moles in the gas mixture.
We need to calculate the number of moles of each element first;
Number of moles = 
Molar mass of Helium = 4g/mol
Molar mass of Neon = 20g/mol
Molar mass of Argon = 40g/mol
Number of moles of He = 
= 0.16moles
Number of moles of Ne = 
= 0.58moles
Number of moles of Ar = 
= 0.19moles
Total number of moles = 0.16moles + 0.58moles + 0.19moles = 0.93moles
Mole fraction Neon = 
= 0.2
