Answer:
189.2 KJ
Explanation:
Data Given
wavelength of the light = 632.8 nm
Convert nm to m
1 nm = 1 x 10⁻⁹
632.8 nm = 632.8 x 1 x 10⁻⁹ = 6.328 x 10⁻⁷m
Energy of 1 mole of photon = ?
Solution
Formula used
E = hc/λ
where
E = energy of photon
h = Planck's Constant
Planck's Constant = 6.626 x 10⁻³⁴ Js
c = speed of light
speed of light = 3 × 10⁸ ms⁻¹
λ = wavelength of light
Put values in above equation
E = hc/λ
E = 6.626 x 10⁻³⁴ Js ( 3 × 10⁸ ms⁻¹ / 6.328 x 10⁻⁷m)
E = 6.626 x 10⁻³⁴ Js (4.741 x 10¹⁴s⁻¹)
E = 3.141 x 10⁻¹⁹J
3.141 x 10⁻¹⁹J is energy for one photon
Now we have to find energy of 1 mole of photon
As we know that
1 mole consists of 6.022 x10²³ numbers of photons
So,
Energy for one mole photons = 3.141 x 10⁻¹⁹J x 6.022 x10²³
Energy for one mole photons = 1.89 x 10⁵ J
Now convert J to KJ
1000 J = 1 KJ
1.89 x 10⁵ J = 1.89 x 10⁵ /1000 = 189.2 KJ
So,
energy of one mole of photons = 189.2 KJ
Answer:
t = 37.1 s
Explanation:
The equation for the reaction is given as;
2 N2O5(g) --> 4 NO2 + O2
Initial: 0.110 - -
change: -2x +4x +x
Final: 0.110 - 2x +4x +x
But final = 0.150atm;
0.110 - 2x + 4x + x = 0.150 atm
3x = 0.150 - 0.110
x = 0.0133 atm
Pressure in reactant side;
0.110 - 2x
0.110 - 2 (0.0133) = 0.0834 atm
The integral rate law expression is given as;
ln ( [A] / [Ao] ) = -kt
k = rate constant = 7.48*10^-3*s-1
ln (0.0834/0.11) = (7.48*10^-3) t
upon solving, t = 37.1 s