Final answer:
An elementary particle is a basic building block of matter, with examples like electrons and quarks, and they come in types called fermions and bosons. An antiparticle shares the same mass as its particle counterpart but possesses an opposite electric charge. When particles and antiparticles come into contact, they annihilate each other, releasing energy.
Step-by-step explanation:
An elementary particle is a fundamental constituent of matter, which is not itself composed of other particles. Common examples include electrons, quarks, and neutrinos. These particles fall into two categories: fermions and bosons, with fermions making up matter, while bosons act as force carriers.
An antiparticle has the same mass as its corresponding particle but with opposite electric charge and other quantum numbers. When a particle and antiparticle meet, they annihilate each other, releasing energy usually in the form of photons. This process is known as annihilation. The existence of antiparticles is confirmed through high-energy physics experiments, showing that for every type of charged particle, there is a counterpart with an opposite charge.
Due to their inherent properties, elementary particles are key to understanding the fundamental forces and structures within the universe. Antiparticles, despite being similar to their matter counterparts, cannot survive for extended periods in a world composed of ordinary matter because of annihilation.