Answer
2.7956 * 10^19 photons
Givens
- Wavelength = λ = 525 * 10^-9 meters [1 nmeter = 1*10^-9 meters]
- c = 3 * 10^8 meters
- E = ???
- W = 100 watts
- t = 1 second
- h= plank's Constant = 6.26 * 10^-34 J*s
Formula
E = h * c / λ
W = E / t
Solution
E = 6.26 * 10^-34 j*s * 3 * 10^8 m/s /525 * 10^-9 (m)
The meters cancel out. So do the seconds. You are left with Joules as you should be.
E = 3.577 * 10^-18 Joules
What you have found is the energy of 1 photon.
Now you have to find the Joules from the watts.
W = E/t
100 * 1 second = 100 joules
1 photon contains 3.577 * 10 ^ - 18 Joules
x photon = 100 joules
1/x = 3.577 * 10^-18 / 100 Cross multiply
100 = 3.577 * 10 ^ - 18 * x Divide both sides by 3.577 * 10 ^ - 18
100/3.577 * 10 ^ - 18 = 3.577 * 10 ^ - 18x / 3.577 * 10 ^ - 18
2.7956 * 10^19 photons = x
Where are the equations ..
Sorry....
Answer is: sulfuric acid is the limiting reactant.
Chemical reaction: 3H₂SO₄ + 2Al(OH)₃ → Al₂(SO₄)₃ + 6H₂O.
m(H₂SO₄) = 34 g.
n(H₂SO₄) = m(H₂SO₄) ÷ M(H₂SO₄).
n(H₂SO₄) = 34 g ÷ 98 g/mol.
n(H₂SO₄) = 0,346 mol.
m(Al(OH)₃) = 33 g.
n(Al(OH)₃) = 33 g ÷ 78 g/mol.
n(Al(OH)₃) = 0,423 mol.
From chemical reaction: n(H₂SO₄) : n(Al(OH)₃) = 3 : 2.
