When water receives an electron from a metal, the water molecule becomes unstable. it splits up into a neutral hydrogen atom and a oh- ion. the neutral hydrogen atoms, each with one electron, randomly wander around until they find each other. this random wandering around is referred to as

The reaction will be like

Now these H will wonder around means they will diffuse here and there (the random transnational movement of particles is known as diffusion) and once the two hydrogen atoms come across each other they will form bond and will form hydrogen molecule

so answer is : diffusion

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

no but i do not usually comment or use my voice that much when it comes to social media