If δh = -70.0 kj and δs = -0.500 kj/k , the reaction is spontaneous below a certain temperature. calculate that temperature. express your answer numerically in kelvins.

Answer is: temperature must be less than 140 K.
Gibbs free energy (G) determines if reaction will proceed spontaneously. If the value of G is a negative, the reaction is spontaneous. ΔG = ΔH - T·ΔS.
ΔH = -70.00 kJ.
ΔS = -0.500 kJ/K.
-70 kJ = T · (-0.5 kJ/K).
T = -70.00 kJ ÷ (-0.500 kJ/K).
T = 140 K. 

The color emitted from a hydrogen spectrum is not white because only colors with certain energy levels can be observed.

Explanation:

White light is generally a combination of seven colors having different wavelengths from the range of 400nm to 700nm, with violet having the wavelength of 700nm and red having 400nm. This shows that white light cannot be given a separate wavelength.

During the hydrogen emission spectrum, the colors with higher wavelengths are observed in the emission and thus there is no white light.