Hair is dead skin cells that pile on top of each other to "grow".
The energy transformations are similar because they result into radiant energy.
As for the lamp, Electrical energy is transformed into light when the filament
or mercury vapor glows on passage of current.
The fire- chemical energy is turned to light energy during the combustion of carbon. Both products comprise of ultraviolet radiation which is a form of radiant energy.
Molarity is simply the ratio of the number of moles of a
substance over the total volume of the solution. Assuming that the addition of
0.850 moles does not change the overall volume of 1.70 L, therefore molarity is
simply:
Molarity = 0.850 moles / 1.70 L = 0.5 moles / L = 0.5 M
The mass of oxygen and hydrogen must be equal to the mass of the substance they create the water. So if the hydrogen is 2.8 g the oxygen must account for the rest of the mass. Basically just subtract 25.4-2.8=mass of oxygen