Hi there!
We can use the following conversions to solve:
Total mass --> amount of mols --> amount of atoms (Avogadro's number)
Begin by calculating the amount of boron trifluoride in 3.61 grams:
3.61 g * (1 mol BF₃ / 67.8 g) ≈ 0.0532 mol BF₃
Use avogadro's number to convert:
0.0532 mol * 6.02× 10²³atoms / 1 mol = 3.203 × 10²² atoms
Answer:
Your correct one is the 3rd one!
I'm assuming you wanted this equation balanced? If you typed it correctly, it's already balanced for you. :)
<span>350 nanometers
We first need to calculate how much energy is needed to ionize a single atom. So divide the kilojoules/mol energy value by avogadro's number.
342 kj/mol / 6.0221409x10^23 = 5.67904x10^-19 Joules
So we need a photon with 5.67904x10^-19 Joules of energy. The equation to express the energy of a photon is
E = hc/w
where
h = Planck constant (6.626070040Ă—10â’34 Js)
c = speed of light (299792458 m/s)
w = wavelength of photon
Solving for w
E = hc/w
Ew = hc
w = hc/E
Substituting known values
w = 6.626070040Ă—10^â’34 Js * 299792458 m/s / 5.67904x10^-19 J
w = 1.9864458x10^-25 Jm / 5.67904x10^-19 J
w = 3.497855x10^-7 m
w = 3.50x10^-7 m
w = 350 nm</span>
The answer is A
explanation:
We know that the atomic weight of carbon is 12 grams and that of oxygen is 16 grams. Hence we have calculated the mass 5 of carbon in carbon dioxide to be 27.27%.
