The answer is D
Because it is kinda basic
The correct option is D.
Because liquids flow, they can assume the shape of any container in which they are pour. Liquids are able to flow because the particles in liquid move around one another easily. When a liquid is pour inside a container, the container limit the fluidity of the liquid particles, so the liquid take up the shape of the container.<span />
Hydrogen fuel works on the principle of making water by H2 and O2 !!
At the cathode (negative electrode): H2(g)-2e →2H+(aq)
At the anode (positive electrode): 4H+(aq) + O2(g) + 4e– → 2H2O(g)
* As there is no harmful gasses evolve, and only water is formed so these cells are clean and healthy to use !!
(ADDITIONAL)
and remember these are 90-98% efficient !! as compare to petrol or diesel that are 50-60% efficient !!
Hydrogen fuel cells are used in Space programs to make pure water and other purposes !!
