Answer:
Explanation:
So , these molecules would want to fill up their shell in order to become stable, which means they would want a total of 8 electrons.
As you can see in the first example, the Carbon has 4 electrons (one dot on each side of the C), however this is not enough as it has not reached 8, so it is unstable. The Carbon would want a full pair of electrons, however it only has a lone electron as there is only one electron per side.
To become stable, it would require 4 more electrons, and as you can see, there are 4 hydrogens, which have one electron each. that means there is a total of 4 hydrogens.
So, the hydrogens and carbon would bond, and the Hydrogen would share one of its electrons to the carbon so it can have a full pair.
Same concept for ammonia
Nitrogen has 5 electrons (meaning it requires 3 more to reach 8) , and 3 of the electrons are lone and need one more to complete the pair. So, the Hydrogen would provide these 3 electrons by joining up with N where there is only one dot on the N.
Hope it makes sense ,
you could search "electron dot diagram for NH3 " to see how it looks