Israel, as they refuse to acknowledge they have the weapons; and North Korea.
USA, Russia, UK, PRC, France, India, Pakistan, North Korea are known for having nuclear weapon. Israel probably also owns nuclear weapon but never officialy declared it.
The meaning of the word nuclear weapon, is a weapon that has a nuclear warhead on it.
United States and Israel, and possibly other nations.
Israel Weapon Industries was created in 2005.
This nuclear weapon is called an atomic bomb or a nuclear bomb
USA, Russia, UK, France, China, India, Pakistan, Israel. Query on North Korea - ask CIA.
Nuclear weapon detonations
If by "bomb" you mean a conventional explosive weapon, then the nuclear weapon is more powerful.
nuclear chemicals such as plutonium
No, while it is generally beleved that Israel does have Atomic weapons, this has never been confimed by Israel. Israel officially refuses to confirm or deny their existence.Meier did say Israel would use "every weapon available" to defend themselves.
No. LLNL even tested several Uranium-Hydride bombs in the 1950s. Even though their computer models said the devices should explode, none gave a nuclear yield. One could use the waste from the reactor as a Radiological Weapon, but the reactor itself is not useful as a weapon.