You need to use Avogadro's constant to convert from atoms of carbon to moles of carbon.
1.71*10^24 atoms C * (1 mole/6.022*10^23 atoms) = 2.84 moles of carbon
Answer:
A
Explanation:
A formal charge (FC) is the charge assigned to an atom in a molecule, assuming that electrons in all chemical bonds are shared equally between atoms, regardless of relative electronegativity(Wikipedia).
The formal charge on an atom in a molecule reflects the electron count associated with the atom compared to the isolated neutral atom(University of Calgary).
Looking at all the structures listed A-E for SeO2F2, only structure A minimizes the formal charges for each atom in SeO2F2.
To solve the concentration, it is equal to the mass of the calcium ions divided by the total mass of the solution.
C = mass of ions / mass solution
C = ( 8.5 x 10 ^-3 g ) / 490 g
C = 1.7 x 10^-5
since the choices are in ppm, multiply it by 10^6
C = (1.7 x 10^-5 ) 10^6
C = 17 ppm
Answer:
A = 8
B = 8
C = Oxygen (O)
D = 26
E = 30
F = Iron (Fe)
Explanation:
protons neutrons atomic number mass number element
A 7 B 15 C
D E 26 56 F
mass number = protons + neutrons
E = 56 - 26 = 30
A = 15 - 7 = 8
protons = atomic number
B = 8
D = 26
From atomic number:
C = Oxygen (O)
F = Iron (Fe)
Answer:
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Explanation:
Hope this helps:)