You can't. The only way to get Raichu in Pokemon yellow is to trade your Pikachu to another game, give it a thunderstone, and then trade it back. I don't suggest this however, as once it is evolved into Raichu it will no longer follow you around in-game. Your best bet - if you want to take the time - is to catch a new pikachu (not available in yellow) on another game and use the thunderstone there and then trade it.
Pikachu will evolve into Raichu when given a thunder stone. If you mean Ash's Pikachu, then it very unlikely he will evolve his Pikachu, as Pikachu is the Pokemon Franchise's mascot.
Pikachu turns into Raichu.
Raichu is the last form of the Pikachu family.
Raichu
You cannot find any wild Raichu in Pokémon Ruby however you can find wild Pikachu in the Safari Zone and then you can use a Thunder Stone item in order to evolve it into Raichu additionally you can trade for Raichu or you can trade with another trainer that has caught Pikachu and you can arrange a trade with them so you can get Pikachu and then you can evolve it into Raichu with the use of a Thunder Stone.
Well Raichu isn't available as a wild Pokemon in any of the games, so evolve Pikachu, or trade a Pokemon for Raichu.
A Pikachu evolves from a Pichu.
Raichu is the evolved form of Pikachu. To get a Raichu, use a Thunder Stone on a Pikachu.
No, Raichu won't be Pikachu-colored if you evolve your Pikachu-colored Pichu into a Raichu, it'll look like a regular Shiny Raichu.
Pikachu evolves into Raichu. To evolve it, you have to use a Thunderstone on it.
find a thunderstone and use it on pikachu then your pikachu will evolve into the powerful max evolution raichu
Raichu never evolves. Unless you meant Pikachu, which evolves into Raichu. Or Pichu, who isn't in Leafgreen but evolves into Pikachu, then Raichu.
pichu, pikachu, then raichu
Pikachu ONLY evolves into a Raichu when you give it a Thunderstone.
pikachu into raichu eevee into jolteon
Ash will never get a Raichu as he has a Pikachu and that Pikachu will never evolve into a Raichu because it is Pokémon's mascot.