Answer:
the mixture or solution is called homogeneous mixture
varying composition is not a property of a pure substance
We first calculate the energy contained in one photon of this light using Planck's equation:
E = hc/λ
E = 6.63 x 10⁻³⁴ x 3 x 10⁸ / 590 x 10⁻⁹
E = 3.37 x 10⁻²² kJ/photon
Now, one mole of atoms will excite one mole of photons. This means that 6.02 x 10²³ photons will be excited
(3.37 x 10⁻²² kJ/photon) x (6.02 x 10²³ photons / mol)
The energy released will be 202.87 kJ/mol
The mean is simply the arithmetic average of all your raw data. This can be solved methodically by summing up all of the raw data points that you have. Take note how many raw data points you used, because this will be used to divide the sum. You will obtain the mean.